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| موضوع: كتاب Handbook of Plastics Joining - A Practical Guide الأربعاء 29 نوفمبر 2023, 10:57 am | |
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أخواني في الله أحضرت لكم كتاب Handbook of Plastics Joining - A Practical Guide Michael J. Troughton
و المحتوى كما يلي :
Table of Contents Introduction .i How To Use This Book ii Plastics Joining Processes Heated Tool Welding - Chapter 1 Process .1 Processing Parameters .3 Materials 4 Weld Microstructure .4 Effects of Ageing on Weld Strength .5 Variants of Hot Tool Welding .5 Equipment 6 Advantages and Disadvantages 6 Applications .7 Hot Gas Welding - Chapter 2 Process 9 Processing Parameters .10 Materials 10 Joint Design .11 Equipment 11 Advantages and Disadvantages 13 Applications .13 Vibration Welding - Chapter 3 Process 15 Processing Parameters .16 Materials 17 Weld Microstructure .18 Cross-Thickness Welding 19 Equipment 20 Orbital Vibration Welding .22 Advantages and Disadvantages 22 Joint Design .24 Applications .25 Spin Welding - Chapter 4 Process 29 Processing Parameters .29 Materials 31 Weld Microstructure .32 Variants of Spin Welding .32 Equipment 32 Advantages and Disadvantages 33 Joint Design .33 Applications .34Ultrasonic Welding - Chapter 5 Process 35 Processing Parameters .37 Ultrasonic Weldability of Materials .40 Joint Design .45 Ultrasonic Equipment .53 Advantages and Disadvantages 55 Applications .56 Ultrasonic Welding Tips .57 Ultrasonic Inserting 59 Ultrasonic Spot Welding 61 Ultrasonic Staking 61 Ultrasonic Stud Welding 65 Ultrasonic Swaging 65 Ultrasonic Bonding .65 Ultrasonic Slitting .66 Ultrasonic Scan Welding 66 Ultrasonic Degating .66 Induction Welding - Chapter 6 Process 67 Electromagnetic Materials .68 Materials To Be Joined 69 Equipment 69 Work Coil Design .69 Joint Design .71 Advantages and Disadvantages 72 Applications .72 Radio Frequency Welding - Chapter 7 Process 75 Heat Generation 75 Equipment 76 Materials 77 Advantages and Disadvantages 78 Applications .78 Microwave Welding - Chapter 8 Process 79 Processing Parameters .80 Materials 81 Equipment 82 Advantages and Disadvantages 82 Resistance Welding - Chapter 9 Process 83 Processing Parameters .84 Materials 85 Joint Design .85 Equipment 86 Advantages and Disadvantages 86 Applications .86Extrusion Welding - Chapter 10 Process 87 Processing Parameters .87 Weld Microstructure .88 Equipment 89 Advantages and Disadvantages 89 Applications .89 Electrofusion Welding - Chapter 11 Process 91 Processing Parameters .92 Materials 93 Equipment 93 Advantages and Disadvantages 94 Applications .94 Infrared Welding - Chapter 12 Process 95 Processing Parameters .96 Materials 97 Microstructure 98 Variants of Infrared Welding 98 Equipment 99 Advantages and Disadvantages 99 Applications .100 Laser Welding - Chapter 13 Process 101 Processing Parameters .102 Materials 103 Weld Microstructure .103 Joint Design .103 Equipment 104 Advantages and Disadvantages 104 Applications .104 Mechanical Fastening - Chapter 14 Process 105 Machine Screws, Nuts, Bolts, & Washers .105 Self-Tapping Screws 107 Molded-In Threads .113 Inserts 114 Press or Interference Fits 119 Snap-Fits .121 Rivets .133 Staking .134Chemical Bonding - Adhesive and Solvent Bonding - Chapter 15 Mechanism of Bonding 137 Types of Adhesives .140 Hot Melt Adhesives 140 Acrylic Adhesives 141 Epoxy Adhesives 144 Elastomer Adhesives .145 Types of Solvents 146 Surface Preparation Methods 147 Mechanical Treatments .147 Chemical Cleaning Treatments .148 Surface Modification 148 Electrical Discharge Treatments 150 Other Surface Preparation Techniques .151 Factors Affecting Adhesive and Solvent Bonding 152 Joint Design .155 Equipment and Application Methods .159 Advantages and Disadvantages 160 Applications .162 Adhesive Bonding Tips 163 Thermoplastics Acetal Resin Acetal Resin - Chapter 16 165 Acetal Copolymer - Chapter 17 .171 Acrylic Resin Acrylic Resin - Chapter 18 .175 Cellulosic Plastic Cellulose Propionate - Chapter 19 .183 Fluoroplastic Fluoropolymer - Chapter 20 .185 Ethylene-Tetrafluoroethylene Copolymer (ETFE) - Chapter 21 .187 Fluorinated Ethylene-Propylene Copolymer (FEP) - Chapter 22 .191 Perfluoroalkoxy Resin (PFA) - Chapter 23 193 Polytetrafluoroethylene (TFE) - Chapter 24 .195 Polyvinylidene Fluoride (PVDF) - Chapter 25 197 Ionomer Ionomer - Chapter 26 .201 Polyamide Nylon - Chapter 27 .203 Amorphous Nylon - Chapter 28 .209 Nylon 12 - Chapter 29 211 Nylon 6 - Chapter 30 213 Nylon 612 - Chapter 31 217 Nylon 66 - Chapter 32 219 Polyarylamide - Chapter 33 .223 Polyphthalamide (PPA) - Chapter 34 .225 Polycarbonate Polycarbonate (PC) - Chapter 35 231Polyester Thermoplastic Polyester - Chapter 36 .265 Polybutylene Terephthalate (PBT) - Chapter 37 267 Polyethylene Terephthalate (PET) - Chapter 38 287 Polycyclohexylenedimethylene Ethylene Terephthalate (PETG) - Chapter 39 .291 Liquid Crystal Polymer (LCP) - Chapter 40 .293 Polyimide Polyimide - Chapter 41 297 Polyamideimide (PAI) - Chapter 42 .301 Polyetherimide (PEI) - Chapter 43 .305 Polyketone Polyaryletherketone (PAEK) - Chapter 44 .313 Polyetheretherketone (PEEK) - Chapter 45 .317 Polyetherketone (PEK) - Chapter 46 .321 Polyolefin Polyethylene (PE) - Chapter 47 .323 Low Density Polyethylene (LDPE) - Chapter 48 327 Medium Density Polyethylene (MDPE) - Chapter 49 .329 High Density Polyethylene (HDPE) - Chapter 50 .331 Ultrahigh Molecular Weight Polyethylene (UHMWPE) - Chapter 51 .337 Polyethylene Copolymer - Chapter 52 .341 Ethylene-Vinyl Acetate Copolymer (EVA) - Chapter 53 .343 Polyethylene-Acrylic Acid Copolymer (EAA) - Chapter 54 345 Polymethylpentene (PMP) - Chapter 55 347 Polypropylene (PP) - Chapter 56 .349 Polypropylene Copolymer (PP Copolymer) - Chapter 57 363 Polyphenylene Ether Polystyrene Modified Polyphenylene Ether (PPO and PPE) - Chapter 58 367 Polyphenylene Sulfide Polyphenylene Sulfide (PPS) - Chapter 59 383 Polysulfone Polysulfone (PSO) - Chapter 60 387 Polyethersulfone (PES) - Chapter 61 399 Styrenic Resin Acrylonitrile-Butadiene-Styrene Copolymer (ABS) - Chapter 62 .407 Acrylonitrile-Styrene-Acrylate Copolymer (ASA) - Chapter 63 .417 Polystyrene (PS) - Chapter 64 .421 General Purpose Polystyrene (GPPS) - Chapter 65 .425 Impact Resistant Polystyrene (IPS) - Chapter 66 427 Styrene-Acrylonitrile Copolymer (SAN) - Chapter 67 .431 Styrene-Maleic Anhydride Copolymer (SMA) - Chapter 68 .435 Styrene-Butadiene Copolymer (Styrene Butadiene) - Chapter 69 .441 Polyurethane Rigid Thermoplastic Urethane (RTPU) - Chapter 70 .443 Vinyl Resin Polyvinyl Chloride (PVC) - Chapter 71 445Plastic Alloy Acrylic Resin/Polyvinyl Chloride Alloy (Acrylic/PVC) - Chapter 72 453 Acrylonitrile-Butadiene-Styrene Copolymer/Polyvinyl Chloride Alloy (ABS/PVC) - Chapter 73 .455 Polycarbonate/Acrylonitrile-Butadiene-Styrene Copolymer Alloy (PC/ABS) - Chapter 74 .457 Polycarbonate/Polyester Alloy - Chapter 75 461 Polycarbonate/Polbutylene Terephthalate Alloy (PC/PBT) - Chapter 76 .463 Polycarbonate/Polyethylene Terephthalate Alloy (PC/PET) - Chapter 77 .465 Polyethylene Terephthalate/Polbutylene Terephthalate Alloy (PET/PBT) - Chapter 79 469 Polystyrene Modified Polyphenylene Ether/Nylon 6 Alloy (PPE/Nylon) - Chapter 80 .471 Polyvinyl Chloride Alloy (PVC Alloy) - Chapter 81 .473 Thermoplastic Elastomers Generic Thermoplastic Elastomer Thermoplastic Elastomer (TPE) - Chapter 82 475 Olefinic Thermoplastic Elastomer Olefinic Thermoplastic Elastomer (TPO) - Chapter 83 477 Polyester Thermoplastic Elastomer Polyester Thermoplastic Elastomer (Polyester TPE) - Chapter 84 479 Styrenic Thermoplastic Elastomer Styrenic Thermoplastic Elastomer (Styrenic TPE) - Chapter 85 483 Urethane Thermoplastic Elastomer Urethane Thermoplastic Elastomer (TPUR) - Chapter 86 .485 Thermoplastic Polyester-Polyurethane Elastomer (TPAU) - Chapter 87 .487 Thermoplastic Polyether-Polyurethane Elastomer (TPEU) - Chapter 88 .489 Vinyl Thermoplastic Elastomer Polyvinyl Chloride Polyol (pPVC) - Chapter 89 491 Thermosets Diallyl Phthalate Polymer Diallyl Phthalate Polymer (DAP) - Chapter 90 .495 Epoxy Resin Epoxy Resin - Chapter 91 497 Phenolic Resin Phenol-Formaldehyde Copolymer - Chapter 92 499 Polyester Thermoset Polyester - Chapter 93 .501 Reaction Injection Molding Systerm (RIM) Polyurethane Reaction Injection Molding System (PU RIM) - Chapter 94 503 Vinyl Ester Vinyl Ester Resin - Chapter 95 505 Polycarbonate/Glycol Modified Polycyclohexylenedimethylene Terephthalate Alloy - Chapter 78 467Rubbers Ethylene Propylene Rubber (EPR) Ethylene-Propylene-Diene Copolymer (EPDM) - Chapter 96 507 Fluoroelastomer Vinylidene Fluoride-Hexafluoropropylene Copolymer (FKM) - Chapter 97 .509 Polyurethane Urethane (PU) - Chapter 98 .511 Rubber Alloy PE Copolymer/ Fluoroelastomer Alloy - Chapter 99 513 Appendices Glossary of Terms .515 Indicies Reference Index 551 Figure Index .561 Table Index 569 Supplier Directory 573 General Index 579 Glossary of Terms ABS See acrylonitrile butadiene styrene polymer. ABS nylon alloy Thermoplastic alloy of ABS and nylon suitable for injection molding. Has properties similar to ABS but considerably higher elongation at yield. ABS polycarbonate alloy Thermoplastic alloy of ABS and polycarbonate suitable for injection molding and extrusion. Has properties similar to ABS. Used in automotive applications. ABS polyurethane alloy Thermoplastic alloy of acrylonitrile butadiene styrene and polyurethane. absolute density See density. absolute gravity See density. accelerator A chemical substance that accelerates chemical, photochemical, biochemical, etc. reaction or process, such as crosslinking or degradation of polymers, that is triggered and/or sustained by another substance, such as curing agent or catalyst, or environmental factor, such as heat, radiation or a microorganism. Also called promoter, cocatalyst. acetal See acetal resin. acetal resin Acetal resins are thermoplastics prepared either by homopolymerization of formaldehyde or its trimer, trioxane, or by copolymerization of trioxane with other monomers, such as ethylene oxide. Acetals have high impact strength, stiffness, and yield stress; low friction coefficient and gas and vapor permeability; good dimensional stability and dielectric properties; high fatigue strength; and good retention of properties at elevated temperatures. The homopolymer has higher heat deflection temperature but lower continuous use temperature than copolymers. All acetals have poor resistance to acids and homopolymers also show poor resistance to alkalies. Acetals are subject to UV degradation, are flammable, and are difficult to bond. Processed by injection and blow molding and extrusion. Used in mechanical parts such as gears and bearings, automotive parts such as window cranks and trim fasteners; appliances; pump housings, shower heads, and other plumbing applications; and electronics such as connectors. Also called POM, polyoxymethylene, polyformaldehyde, acetal. acetone A volatile, colorless, highly flammable liquid with molecular formula CH3COCH3. Acetone has autoignition temperature 537°C, mixes readily with water and some other solvents and is moderately toxic. Acetone dissolves most thermoplastics and some thermosets. Used as organic synthesis intermediate, e.g., in the manufacture of bisphenol A and antioxidants, as solvent in paints and acetate fiber spinning and for cleaning of electronic parts. Also called dimethyl ketone. acrylate resin See acrylic resin. acrylate styrene acrylonitrile polymer Acrylic rubber-modified thermoplastic having high outdoor weatherability, e.g., retention of color, gloss, and impact and tensile properties. The material offers high gloss, good heat and chemical resistance, great toughness and rigidity, and very good antistatic properties. It is compatible with other polymers such as PVC and polycarbonate and processable by (co)extrusion, thermoforming, injection molding, structural foam molding, and extrusion-blow molding. Drying is necessary because the material is mildly hygroscopic. Used in building and construction, leisure and recreation, and automotive applications when there is a demand for good weatherability, e.g., commercial siding, exterior auto trim, outdoor furniture. Also called ASA, acrylonitrile styrene acrylate polymer, acrylic styrene acrylonitrile polymer. acrylate styrene acrylonitrile polymer polyvinyl chloride alloy Thermoplastic alloy of an acrylate styrene acrylonitrile polymer with polyvinyl chloride. acrylic epoxy resin See vinyl ester resin. acrylic ethylene rubber See ethylene acrylic rubber. acrylic resin The class of thermoplastics comprised of homopolymers and copolymers of alkyl (meth)acrylates. The most common monomers used are methyl and ethyl (meth)acrylates; the comonomers include other unsaturated monomers. The acrylic resins offer excellent optical clarity, weatherability and resistance to sunlight, outstanding surface hardness, good chemical resistance, rigidity, good impact strength, excellent dimensional stability, and low mold shrinkage. They have poor solvent resistance, are subject to stress cracking, are combustible, and have low flexibility and thermal stability. The acrylic resins can be cast in sheets, rods, or tubing; extruded into sheets or profiles; injection molded; thermoformed; and coated. The applications include transparent items such as lenses, automotive trim, household items, light fixtures, conformed coatings on printed circuit boards, and medical devices. Also called polyacrylate, acrylate resin. acrylic resin polyvinyl chloride alloy A thermoplastic alloy of an acrylic resin and polyvinyl chloride. acrylic styrene acrylonitrile polymer See acrylate styrene acrylonitrile polymer. acrylonitrile butadiene rubber See nitrile rubber. acrylonitrile butadiene styrene polymer ABS resins are thermoplastics comprised of a mixture of styrene-acrylonitrile copolymer (SAN) and SAN-grafted butadiene rubber. They have high impact resistance, toughness, rigidity and processability, but low dielectric strength, continuous service temperature, and elongation. Outdoor use requires protective coatings in some cases. Plating grades provide excellent adhesion to metals. Processed by extrusion, blow molding, thermoforming, calendaring and injection molding. Used in household appliances, tools, nonfood packaging, business machinery, interior automotive parts, extruded sheet, pipe and pipe fittings. Also called ABS. acrylonitrile copolymer Acrylonitrile copolymers are thermoplastics prepared by copolymerization of acrylonitrile with minor amounts of other unsaturated monomers. The class of acrylonitrile copolymers include ASA, ABS, SAN, and nitrile resins. In a narrower sense the term acrylonitrile copolymers is often used to denote (high) nitrile (barrier) resins. These resins have good gas barrier properties, chemical resistance, and taste and odor retention properties. These resins have moderately high tensile properties and good impact properties when rubber modified or oriented. Processed by extrusion, injection molding, and thermoforming. Used mainly in food and nonfood packaging. FDA approved for direct contact with food with some limitations.acrylonitrile methyl acrylate copolymer A thermoplastic polymer of acrylonitrile and methyl acrylate. acrylonitrile rubber See nitrile rubber. acrylonitrile styrene acrylate polymer See acrylate styrene acrylonitrile polymer. activation energy An excess energy that must be added to an atomic or molecular system to allow a process, such as diffusion or chemical reaction, to proceed. adherend A body held to another body, usually by an adhesive or solvent. A part or detail being prepared for bonding. adhesion promoter A coating applied to a substrate prior to adhesive application, in order to improve adhesion of the material, such as a plastic. Also called primer. adhesive A material, usually polymeric, capable of forming permanent or temporary surface bonds with another material as is or after processing such as curing. Used for bonding and joining. Many classes of adhesives include hot-melt, pressure-sensitive, contact, UV cured, emulsion, etc. adhesive abrasion In adhesive bonding, a surface preparation technique in which the part surface is mechanically abraded in the presence of liquid adhesive. Abraded, adhesive-coated adherends are then mated, and adhesive is allowed to cure. It is speculated that abrasion in the presence of adhesive creates free radicals that react directly with the adhesive; when abrasion is performed in the absence of adhesive, the generated free radicals are scavenged by oxygen in air before adhesive is applied. Adhesive abrasion is commonly used on fluorocarbons; bond strengths of Teflon (PTFE) were increased about 700% using this technique. adhesive bonding A method of joining two plastics or other materials in which an adhesive is applied to the part surfaces. Bonding occurs through mechanical or chemical interfacial forces between the adhesive and adherend and / or by molecular interlocking. Surface preparation of the adherends and curing of the adhesive may be required. adhesive failure Failure of an adhesive bond at the adhesiveadherend interface. An example is an adhesive failure that leaves adhesive all on one adherend, with none on the other adherend. Adhesive failure is less desirable than cohesive failure because it is indicative of a joint with lower adhesive strength. See also cohesive failure. adiabatic A process in which there is no gain or loss of heat from the system to the environment. For plastics, although not completely correct, it is used to describe a mode of extrusion in which no external heat is added to the extruder. Heat may be removed from the extruder by cooling in order to keep the output temperature of the melt passing through the extruder constant. Heat input in this process originates from the conversion of mechanical energy of the screw to thermal energy. adipic acid hexanediamine polymer See nylon 66. adsorption Retention of a substance molecule on the surface of a solid or liquid. Also called physical adsorption. advanced styrenic resin See styrenic resin. alpha cellulose See cellulose. amideimide resin See polyimide. amorphous nylon Amorphous nylons are transparent products that typically involve rings in copolymer chains. One amorphous nylon involves 2,4,4- and 2,2,4-trimethylhexamethylene diamine and terephthalic acid. amplitude The maximum displacement of a particle measured from its equilibrium position. annealing A process in which a material, such as plastic, metal, or glass, is heated then cooled slowly. In plastics and metals, it is used to reduce stresses formed during fabrication. The plastic is heated to a temperature at which the molecules have enough mobility to allow them to reorient to a configuration with less residual stress. Semicrystalline polymers are heated to a temperature at which retarded crystallization or recrystallization can occur. antimony pentoxide (SbO5) A white or yellowish powder that melts at 450°C (842°F). Loses oxygen above 300°C (572°F). Soluble in strong bases, forming antimonates; slightly soluble in water; insoluble in acids except for concentrated hydrochloric acid. Derived by reaction of concentrated nitric acid with the metal or trioxide. Used as a flame retardant for textiles and in the preparation of antimonates and other antimony compounds. Also called antimonic anhydride, antimonic acid, stibic anhydride. antimony trioxide (Sb2O3) A white, odorless, crystalline powder that melts at 655°C (1211°F). Soluble in concentrated hydrochloric and sulfuric acids and strong bases; insoluble in water. Amphoteric, a suspected carcinogen. Derived by reaction of ammonium hydroxide with antimony chloride, combustion of antimony in air, or directly from low-grade ores. Used in flameproofing textiles, paper, and plastics, especially polyvinyl chloride; glass decolorizer; paint pigments; staining of copper and iron; opacifiying ceramics; and as a catalyst or intermediate in organic reactions. Also called antimony white, antimony oxide. aramid See polyarylamide. aromatic ester carbonate See aromatic polyester estercarbonate. aromatic polyamide See polyarylamide. aromatic polyester Aromatic polyesters are thermoplastics prepared by polycondensation of aromatic polyol with aromatic dicarboxylic acid or anhydride or by polycondensation of aromatic hydroxycarboxylic acid. They are tough, durable, heat resistant, and offer good dimensional stability, dielectric properties, UVstability, and flame retardance. Chemical resistance of aromatic polyesters is somewhat lower than other engineering plastics. Processing is achieved by injection and blow molding, extrusion, and thermoforming. Thorough drying is required. Uses include automotive housings and trim, electrical wire jacketing, printed circuit boards, appliance enclosures. Also called polyarylate, ARP. aromatic polyester estercarbonate A thermoplastic comprising block copolymer of an aromatic polyester with polycarbonate. It has increased heat distortion temperature, compared to generalpurpose polycarbonate. Also called polyestercarbonate, aromatic polyestercarbonate, aromatic ester carbonate. aromatic polyestercarbonate See aromatic polyester estercarbonate. ARP See aromatic polyester. ASA See acrylate styrene acrylonitrile polymer.ASA PVC alloy Alloy of acrylic styrene acrylonitrile and polyvinyl chloride. aseptic In food processing, a process or condition that renders a processed food product essentially free of microorganisms capable of growing in the food in unrefrigerated distribution and storage conditions. In aseptic food packaging, presterilized containers are filled with aseptic foods, then hermetically sealed in a commercially sterile atmosphere. ASR See styrenic resin. ASTM D1002 An American Society for Testing of Materials (ASTM) standard practice for testing the shear strength of rigid sheet material by tensile loading. Two sections of a rigid sheet material, usually 4 in. in length x 1 in. in width x 0.064 in. in thickness (101.6 x 25 x 1.62 mm) and having suitably treated surfaces, are overlapped 0.5 in. (12.7 mm) and adhesively bonded together in a 0.5 square inch contact area (323 mm2). Both ends are then clamped firmly into the jaws of a tensile testing machine, and the the jaws are moved apart at a speed of 0.05 in./min. (1.3 mm/min.) until joint failure occurs. The failing load, in psi (MPa) and mode of failure (adhesive, cohesive, or mixed) is reported. This is the most commonly used shear test for metal-to-metal structural adhesives. Although it is useful for quality control and comparing different adhesives, failure strength values are not useful for engineering design due to the complex stress distribution pattern in the adhesive with this joint configuration. Also called the lap shear test. Also called lap shear test. ASTM D1761 An American Society for Testing of Materials (ASTM) standard practice for testing the strength and performance of mechanical fasteners in wood. Withdrawal resistance of wood to nails, staples, and screws is measured by recording the maximum load of fasteners withdrawn at a uniform rate of speed by a testing machine. Resistance of nails, staples, and screws to lateral movement is tested by tensile loading. Strength and rigidity of timber joints fastened with bolts or other metal connectors is tested by measuring the deformation of the joint at various intervals of loading. Vertical load capacity and torsional moment capacity of joist hangers is tested by measuring the amount of slip under load. ASTM D4501 An American Society for Testing of Materials (ASTM) standard practice for determining the shear strengths of adhesives used to bond rigid materials by the block shear method. Adhesively bonded blocks, plates, or disks, with flash and fillets removed on the loaded side, are mounted into the shear fixture of a testing machine (capacity not less than 44 kN (10,000lbf)). Test specimens can be any size within the limits of the shearing fixture capacity. The shear fixture is mounted into the testing machine in such a way that one adherend is engaged by the holding block and the other by the shearing tool. A crosshead speed of 1.26 mm/min. (0.05 in./min.) is used for testing. The maximum forces sustained by the specimen is recorded. This test is particularly applicable for testing bonds between ceramic, glass, magnet moldings, and plastic parts with one flat face in which machining is difficult or impractical. average molecular weight See molecular weight. B bar A metric unit of measurement of pressure equal to 1.0E+06 dynes/cm2 or 1.0E+05 pascals. It has a dimension of unit of force per unit of area. Used to denote the pressure of gases, vapors and liquids. barrier material Materials such as plastic films, sheeting, wood laminates, particle board, paper, fabrics, etc. with low permeability to gases and vapors. Used in construction as water vapor insulation, food packaging, protective clothing, etc. base resin melt index See melt index. beading In joining plastics, bending an edge of a flat thermoplastic sheet, using roll(s) with or without heating, or flanging an end of a thermoplastic pipe, using mandrel with or without heating, to form a profile suitable for subsequent joining or assembly. In coating, heavy accumulation of a coating which occurs at the lower edge of a panel or other vertical surface as the result of excessive flowing. bending strength See flexural strength. benzene An aromatic hydrocarbon with six-atom carbon ring, C6H6. Highly toxic and flammable (autoignition point 562°C). A colorless or yellowish liquid under normal conditions (b.p. 80.1°C), soluble in many organic solvents such as ethanol, acetone, tetrachlorocarbon, etc. Used for synthesis of organic compounds. bisphenol A epoxy resin See epoxy resin. bisphenol A fumarate polyester See bisphenol A polyester. bisphenol A polyester A thermoset unsaturated polyester based on bisphenol A and fumaric acid. Also called bisphenol A fumarate polyester. black lead See graphite filler. booster In ultrasonic welding, a mechanical transformer used to increase or decrease the amplitude of the horn. boss A hollow or solid projection used for attachment and support of related components. Properly designed bosses and ribs can provide dimensional stability to the part, while reducing material usage and molding cycle time. In mechanical fastening, the hollow projection into which an insert or screw is driven. Solid bosses are also called studs. breaking elongation See elongation. bursting strength Bursting strength of a material, such as plastic film, is the minimum force per unit area or pressure required to produce rupture. The pressure is applied with a ram or a diaphragm at a controlled rate to a specified area of the material held rigidly and initially flat but free to bulge under the increasing pressure. butadiene styrene block polymer See styrene butadiene block copolymer. butadiene styrene methyl methacrylate polymer See methyl methacrylate butadiene styrene terpolymer. Butanone 2- (CH3COCH2CH3) A colorless liquid with an acetonelike odor. Soluble in benzene, alcohol, ether; partially soluble in water; miscible with oils. Its TLV is 200 ppm in air; it is toxic byinhalation and a dangerous fire risk. Explosive limit in air is 2- 10%. Derived from sulfuric acid hydrolysis of mixed n-butylenes followed by distillation, by controlled oxidation of butane, or by fermentation. Used as a solvent in nitrocellulose coatings and vinyl films and in paint removers, cements and adhesives, manufacture of smokeless powder, cleaning fluids, and acrylic coatings. Used in printing, and as a reagant for organic synthesis. Also called methyl ethyl ketone, MEK, ethyl methyl ketone. Also called methyl ethyl ketone, MEK. butt joint A type of edge joint in which the edge faces of the two parts are at right angles to the other faces of the part. butt joint weld A weld in which the parts are joined using a butt joint. C CA See cellulose acetate. CAB See cellulose acetate butyrate. caprolactam pyrrolidone polymer See nylon 46. carbon black Carbon black is a black colloidal carbon filler made by the partial combustion and/or thermal cracking of natural gas, oil, or another hydrocarbon. Depending upon the starting material and the method of manufacture, carbon black can be called acethylene black, channel black, furnace black, etc. For example, channel black is made by impinging gas flames against steel plates or channel irons, from which the deposit is scraped at intervals. The properties and the uses of each carbon black type can also vary. Thus, furnace black comes in high abrasion, fast extrusion, high modulus, general purpose, and semireinforcing grades among others. Carbon black is widely used as a filler and pigment in PVC, phenolic resins, and polyolefins. It increases the resistance to UV light and electrical conductivity and sometimes acts as a crosslinking agent. Also called colloidal carbon. carbon fiber Carbon fibers are high-performance reinforcement consisting essentially of carbon. They are made by a variety of methods including pyrolysis of cellulosic (e.g., rayon) and acrylic fibers, burning-off binder from a pitch precursor, and growing single crystals (whiskers) via thermal cracking of hydrocarbon gas. The properties of carbon fibers depend on the morphology of carbon in them and are the highest for crystalline carbon (graphite). These properties include high modulus and tensile strength, high thermal stability, electrical conductivity, chemical resistance, wear resistance, and relatively low weight. Used as continuous or short fibers and in mats in autoclave and die molding, filament winding, injection molding, and pultrusion. Carbon fibers are used at a loading levels of 20-60 vol% or more in both thermosets and thermoplastics such as epoxy resins and ABS. Carbon fibers are often used in combination with other fibers such as glass fibers to make hybrid composites. The end products containing carbon fibers include wheel chairs, tennis racquets, auto parts, machine tools, and support structures in electronic equipment. Also called graphite fiber. carbon filler Carbon fillers are a family of fillers based on carbon in various forms, such as carbon black and graphite. Used as a black pigment, to improve lubricity, and to increase electrical conductivity of plastics. Also called powdered carbon, carbon powder. carbon graphite See graphite filler. carbon powder See carbon filler. carbon tetrachloride (CCl4) A colorless liquid with a sweet odor. Miscible with alcohol, ether, chloroform, benzene, solvent naphtha, and most fixed and volatile oils; insoluble in water. Noncombustible. Boils at 76.74°C (170.13°F); freezes at -23°C (- 9.4°F); vapor is 5.3 times heavier than air. Its TLV is 5 ppm in air; it is toxic by ingestion, inhalation, and skin absorption. Decomposes to phosgene at high temperatures. Derived by reaction of carbon disulfide and chlorine in the presence of iron or by chlorination of methane or higher hydrocarbons at 250 - 400°C (752°F). Purified by removal of sulfur chloride using caustic alkali, followed by rectification. Used in metal degreasing, chlorination of organic compounds, the production of semiconductors and solvents (fats, oils, rubber); as a refrigerant and agricultural fumigant. Also called tetrachloromethane, perchloromethane. cast film Film produced by pouring or spreading resin solution or melt over a suitable temporary substrate, followed by curing via solvent evaporation or melt cooling and removing the cured film from the substrate. CE See cellulosic plastic. cellulose Cellulose is a natural carbohydrate polymer of high molecular weight comprised of long chains of D-glucose units joined together by beta-1,4-glucasidic bonds. It is derived from plants such as cotton and trees. It is used to produce cellulose esters and ethers, i.e., cellulosic plastics, but the largest use is in paper manufacture. Cellulose fillers in a narrow sense are usually made from wood pulp. In a broader sense they may include cotton lint, wood flour, lignin, wood chips, and various cellulosic waste such as cotton fiber rejects. Treating wood pulp with alkali results in a colorless filler used in thermosetting resins such as phenolic. Also called pulp, cellulose pulp, alpha cellulose. cellulose acetate Thermoplastic ester of cellulose and acetic acid which is characterized by toughness, gloss, clarity, good processability, stiffness, hardness, good "feel", and dielectric properties. The disadvantages of this ester include poor resistance to solvents, alkaline materials, and fungi, high moisture pickup and permeability, rather low compressive strength, and flammability. It is processed by injection and blow molding and extrusion. The applications include telephone and appliance cases, automotive steering wheels, pens and penciles, tool handles, tubular containers, eyeglass frames, brushes, tapes, sheeting, and signs. Also called CA. cellulose acetate butyrate Thermoplastic mixed ester of cellulose and acetic and butyric acids. Characterized by toughness, gloss, clarity, good processability, low temperature impact strength, dimesional stability, weatherability, good "feel", and dielectric properties. The disadvantages of this ester include poor resistance to solvents, alkaline materials, and fungi, high moisture pickup and permeability, rather low compressive strength, and flammability. It is processed by injection and blow molding and extrusion. The applications include telephone and appliance cases, automotive steering wheels, pens and penciles, tool handles, tubular containers, eyeglass frames, brushes, tapes, sheeting, and signs. Also called cellulose butyrate, CAB. cellulose butyrate See cellulose acetate butyrate. cellulose propionate Thermoplastic ester of cellulose and propionic acid which is characterized by toughness, gloss, clarity, good processability, low temperature impact strength, dimesional stability, weatherability, good "feel", and dielectric properties. The disadvantages of this ester include poor resistance to solvents, alkaline materials, and fungi, high moisture pickup and permeability, rather low compressive strength, and flammability. It is processed by injection and blow molding and extrusion. Theapplications include telephone and appliance cases, automotive steering wheels, pens and penciles, tool handles, tubular containers, eyeglass frames, brushes, tapes, sheeting, and signs. Also called CP. cellulose pulp See cellulose. cellulosic See cellulosic plastic. cellulosic plastic A class of thermoplastics consisting of cellulose esters and ethers. The most important esters are acetates, including mixed esters, and nitrates. The most important ethers are ethyl and carboxymethyl. The cellulosic plastics are characterized by toughness, gloss, clarity, and good processability. In addition, the acetates exhibit good stiffness and hardness, the butyrates and propionates show increased weatherability, low temperature impact strength, and dimensional stability, and all esters have good "feel" and dielectric properties. The disadvantages of the esters include poor resistance to solvents, alkaline materials, and fungi, high moisture pickup and permeability, rather low compressive strength, and flammability. They are processed by injection and blow molding and extrusion. The applications include telephone and appliance cases, automotive steering wheels, pens and pencils, tool handles, tubular containers, eyeglass frames, brushes, tapes, sheeting, and signs. Also called cellulosic, CE. chain scission Breaking of the chainlike molecule of a polymer as a result of chemical, photochemical, etc. reaction such as thermal degradation or photolysis. chamfer A beveled edge or corner; to bevel a sharp edge. chemical saturation Absence of double or triple bonds in a chain organic molecule such as that of most polymers, usually between carbon atoms. Saturation makes the molecule less reactive and polymers less susceptible to degradation and crosslinking. chemical unsaturation Presence of double or triple bonds in a chain organic molecule such as that of some polymers, usually between carbon atoms. Unsaturation makes the molecule more reactive, especially in free-radical addition reactions such as addition polymerization, and polymers more susceptible to degradation, crosslinking and chemical modification. chlorendic polyester A thermoset unsaturated polyester based on chlorendic anhydride. chlorinated polyvinyl chloride Thermoplastics produced by postchlorination of PVC to increase glass temperature and heat deflection under load. Have high chemical resistance, rigidity, flame retardance, tensile strength, and weatherability. Processed by extrusion, injection molding, casting, and calendering. Used in hot and cold water piping and fittings, chemical liquid piping, automotive parts, waste disposal devices, outdoor applications, and glazing beads. Also called PVD, CPVC. chloroprene rubber See neoprene rubber. chlorosulfonated PE rubber See chlorosulfonated polyethylene rubber. chlorosulfonated polyethylene rubber Chlorosulfonated polyethylene rubbers are thermosetting elastomers that contain between 20 and 40% chlorine and approximately 1 to 2% sulfur. They provide resistance to ozone and oxygen attack under sunlight and UV radiation conditions. They are also resistant to deterioration due to heat, chemicals, and solvents. The most common applications for these elastomers are hose, tubing, and sheet goods, soles and heels, life boats and jackets, and windbreakers. Also called CSPE rubber, CSM, chlorosulfonated PE rubber. chopped glass fiber Chopped glass fibers have lengths from 1/8 to 1/2 in. and are made by chopping glass strands containing 8 120 filaments. The individual fibers are bonded together within strands so that they can remain in bundles after chopping. Used widely in bulk molding compounds; and compression, transfer, and injection molding. Also called short glass fiber, medium glass fiber, chopped strand. chopped strand See chopped glass fiber. chromic acid etching In adhesive bonding, a surface preparation technique in which chromic acid is used to introduce oxygenated reactive molecular groups, such as hydroxl, carbonyl, carboxylic, and hydrogen sulfite, to the part surface and to form root-like cavities as sites for mechanical interlocking. Commonly used for polyolefins, ABS, polystyrene, polyphenyleneoxide, and acetals. cobalt napthenate A brown, amorphous powder or bluish-red solid of indefinite composition. Soluble in alcohol, ether, oils; insoluble in water. Combustible. Derived from reaction of cobaltous hydroxide or cobaltous acetate with naphthenic acids. Used as catalyst in bonding rubber to steel and other metals and as a paint and varnish drier. Also called cobaltous napthenate. cobalt-60 One of the unstable isotopes of Co used widely as a source of gamma radiation. cocatalyst See accelerator. coextruded film A film made by coextrusion of 2 or more different or similar plastics through a single die with two or more orifices arranged so that the extrudates merge and weld together into a laminar film before cooling. Each ply of coextruded film imparts a desired property, such as impermeability or resistance to some environment and heat-sealability, usually unattainable with a single material. cohesive failure Failure of an adhesive bond that occurs within the adhesive, leaving adhesive present on both adherends. Optimum failure is 100% cohesive failure, when both shear areas are completely covered. See also adhesive failure. colloidal carbon See carbon black. conditioning Process of bringing the material or apparatus to a certain condition, e.g., moisture content or temperature, prior to further processing, treatment, etc. Also called conditioning cycle. conditioning cycle See conditioning. conduction In heat transfer, migration of energy due to a temperature gradient. Heat energy is transferred by the movement of molecules at hotter or colder temperatures, with different degrees of thermal motion, into colder or hotter regions, respectively. See also radiation convection. contact adhesive An adhesive that will adhere to itself on contact. When applied to both adherends, it forms a bond after drying, without sustained pressure on the adherends. Composed of neoprene or, less commonly, nitrile elastomers. See also pressure sensitive adhesive. continuous glass fiber Continuous glass fibers are strands of filaments (roving) made by melt drawing from various grades of glass. Can be twisted. Used in sheet molding compounds, sprayup lamination, pultrusion, and filament winding. Continuous glass fibers provide fast wetout, even tension, and abrasion resistance during processing. Also called long glass fiber, continuous strand roving, continuous roving, continuous glass roving.continuous glass roving See continuous glass fiber. continuous roving See continuous glass fiber. continuous strand roving See continuous glass fiber. convection The mass movement of particles arising from the movement of a streaming fluid due to difference in a physical property such as density, temperature, etc. Mass movement due to a temperature difference results in heat transfer, as in the upward movement of a warm air current. See also radiation conduction. copolyester See polyester. copolyester thermoplastic rubber See polyester thermoplastic elastomer. copolyester TPE See polyester thermoplastic elastomer. corona discharge treatment In adhesive bonding, a surface preparation technique in which a high electric potential is discharged by ionizing the surrounding gas, usually air. The gas reacts with the plastic, roughening the surface to provide sites for mechanical interlocking and introducing reactive sites on the surface. Functional groups such as carbonyls, hydroxyls, hydroperoxides, aldehydes, ethers, esters, carboxylic acids, and unsaturated bonds have been proposed as reactive sites. Commonly used for polyolefins, corona discharge increases wettability and surface reactivity. In processing plastics, treating the surface of an inert plastic such as polyolefin with corona discharge to increase its affinity to inks, adhesives or coatings. Plastic films are passed over a grounded metal cylinder with a pointed high-voltage electrode above it to produce the discharge. The discharge oxidizes the surface, making it more receptive to finishing. Also called corona treatment. See also plasma arc treatment. corona treatment See corona discharge treatment. Coulombic friction The opposing force that occurs when two dry surfaces are rubbed together, as in vibration and spin welding. Also called external friction. See also internal friction. coupler In ultrasonic welding, a booster that does not affect the amplitude of the horn. Its gain ratio is 1:1. CP See cellulose propionate. CPVC See chlorinated polyvinyl chloride. cracking Appearance of external and/or internal cracks in the material as a result of stress that exceeds the strength of the material. The stress can be external and/or internal and can be caused by a variety of adverse conditions: structural defects, impact, aging, corrosion, etc. or a combination thereof. Also called resistance to cracking, grazing, cracking resistance. See also crazing. cracking resistance See cracking. crazing Appearance of thin cracks on the surface or minute frost-like internal cracks in materials such as plastic as a result of residual stress, impact, temperature changes, degradation, etc. See also cracking creep Time-dependent increase in strain in material, occuring under stress. crosslinked PE See crosslinked polyethylene. crosslinked polyethylene Polyethylene thermoplastic partially crosslinked by irradiation or by the use of chemical additives such as peroxides to improve tensile strength, dielectric properties and impact strength over a wider range of temperatures. Also called crosslinked PE. crosslinking Reaction or formation of covalent bonds between chain-like polymer molecules or between polymer molecules and low-molecular compounds such as carbon black fillers. As a result of crosslinking polymers, such as thermosetting resins, may become hard and infusible. Crosslinking is induced by heat, UV or electron-beam radiation, oxidation, etc. Crosslinking can be achieved ether between polymer molecules alone as in unsaturated polyesters or with the help of multifunctional crosslinking agents such as diamines that react with functional side groups of the polymers. Crosslinking can be catalyzed by the presence of transition metal complexes, thiols and other compounds. crystal polystyrene See general purpose polystyrene. crystal PS See general purpose polystyrene. crystalline melting point The temperature of melting of the crystalline phase of a crystalline polymer. It is higher than the temperature of melting of the surrounding amorphous phase. CSM See chlorosulfonated polyethylene rubber. CSPE rubber See chlorosulfonated polyethylene rubber. CTFE See polychlorotrifluoroethylene. curing A process of hardening or solidification involving crosslinking, oxidizing, and / or polymerization (addition or condensation). cyanoacrylate In adhesive bonding, a highly reactive class of adhesives that cures rapidly at room temperature with trace amounts of moisture as catalysts to form high strength bonds with plastics and metals. cyclohexane (C6H12) A colorless liquid with a pungent odor. Molecular structure is an alicyclic hydrocarbon that can exist in two conformations, the "boat" and "chair", depending on bond angles between carbon atoms. Soluble in alcohol, acetone, benzene; insoluble in water. Boils at 807°C (1485°F); freezes at 6.3°C (43°F). Its autoignition temperature is 473°F (145°C). It is a dangerous fire risk; flammable limit in air is 1.3 - 8.4%. Its TLV is 300 ppm in air; it is moderately toxic by inhalation and skin contact. Derived from crude petroleum or by catalytic hydrogenation of benzene. Used in the production of nylon, in the extraction of essential oils; as a solvent for cellulose ethers, fats, oils, crude rubber, bitumens, resins, waxes; in organic synthesis; as a paint and varnish remover and in glass substitutes. Also called hexamethylene, hexanaphthene, hexalhydrobenzene. cyclohexanone (C6H10O) Cyclohexanone is an oily, water-white to pale yellow liquid with a slight odor of peppermint and acetone. Soluble in organic solvents such as alcohols and ethers, slightly soluble in water. It has an autoignition temperature of 420°C (788°F). Its TLV is 25 ppm in air; it is toxic by inhalation and skin contact. Derived by passing cyclohexanol over copper with air at 138°C (280°F) or by oxidation of cyclohexanol with chromic acid or oxide. Used in the preparation of adipic acid, caprolactam, polyvinyl chloride and its copolymers, and methacrylate ester polymers, and for metal degreasing. Used in wood stains, paint and varnish removers, spot removers, polishes, natural and synthetic resins, lube oil, and other products. Also called pimelic ketone, ketohexamethylene. DDAIP See diallyl phthalate resin. damping In part assembly, to mechanically limit the amplitude of vibration in the parts being assembled. DAP See diallyl phthalate resin. dart impact energy The mean energy of a free-falling dart that will cause 50% failures after 50 tests to a specimen directly stricken by the dart. The energy is calculated by multiplying dart mass, gravitational acceleration and drop height. Also called falling dart impact strength, dart impact strength. dart impact strength See dart impact energy. deflection temperature under load See heat deflection temperature. degradation Loss or undesirable change in properties as a result of aging, chemical reactions, wear, use, exposure, etc. The properties include color, size, strength, etc. See also degradation. density The mass of any substance (gas, liquid or solid) per unit volume at specified temperature and pressure. The density is called absalute when measured under standard conditions, e.g., 760 mmHg pressure and 0°C temperature. Note: For plastics- the weight in air per volume of impermeable portion of the material measured at 23°C according to ASTM D792. Also called mass density, absolute gravity, absolute density. diallyl isophthalate See diallyl phthalate resin. diallyl isophthalate resin See diallyl phthalate resin. diallyl meta phthalate See diallyl meta phthalate resin. diallyl meta phthalate resin Diallyl phthalates are thermoset resins comprising diallyl phthalate prepolymer. Sometimes supplied as a monomer. These resins show excellent moisture resistance, high service temperatures, good retention of electric properties under high temperature and humidity, dimensional stability, chemical resistance (except for phenols and oxidizing acids), and good mechanical strength. The disadvantages include high cost and shrinkage during curing. Cured by peroxide catalysts. Processed by injection, compression, and transfer molding. Used in glass fiber-reinforced plastic articles such as tubing and in the manufacture of automotive distribution caps, electronic connectors, and transformer cases. Also called diallyl meta phthalate. diallyl ortho phthalate See diallyl ortho phthalate resin. diallyl ortho phthalate resin Diallyl phthalates are thermoset resins comprising diallyl phthalate prepolymer. Sometimes supplied as a monomer. These resins show excellent moisture resistance, high service temperatures, good retention of electric properties under high temperature and humidity, dimensional stability, chemical resistance (except for phenols and oxidizing acids), and good mechanical strength. The disadvantages include high cost and shrinkage during curing. Cured by peroxide catalysts. Processed by injection, compression, and transfer molding. Used in glass fiber-reinforced plastic articles such as tubing and in the manufacture of automotive distribution caps, electronic connectors, and transformer cases. Also called diallyl ortho phthalate. diallyl phthalate See diallyl phthalate resin. diallyl phthalate resin Thermoset resins comprised of diallyl (iso)phthalate prepolymer. Sometimes supplied as a monomer. These resins show excellent moisture resistance, high service temperatures, good retention of electric properties under high temperature and humidity, dimensional stability, chemical resistance (except for phenols and oxidizing acids), and good mechanical strength. The disadvantages include high cost and shrinkage during curing. Cured by peroxide catalysts. Processed by injection, compression, and transfer molding. Used in glass fiber-reinforced plastic articles such as tubing and in the manufacture of automotive distribution caps, electronic connectors, and transformer cases. Also called PDAP, diallyl phthalate, diallyl isophthalate resin, diallyl isophthalate, DAP, DAIP. diaphragmming Part flexing that can cause stress, fracturing, or undesirable melting of thin-sectioned, flat parts. Also called "oilcanning", which describes the way the plastic part bends up and down when subjected to ultrasonic energy. dichloroethylene 1,2 (ClCH:CHCl) A colorless liquid with a pleasant odor. Exists as cis and trans stereoisomers. Soluble in most organic solvents; slightly soluble in water. Trans isomer boils at 47 - 49°C (116 - 120°F); cis isomer boils at 58 - 60°C (136 - 140°F) and freezes at -80°C (-112°F). Its TLV is 200 ppm in air; it is toxic by ingestion, inhalation, and skin contact and is an irritant and narcotic at high concentrations. Flammable; a dangerous fire hazard. Used as a solvent for organic compounds and in organic synthesis; in dye extraction, perfumes, lacquers, and thermoplastics. Also called sym-dichloroethylene, acetylene dichloride, dichloroacetylene. dichloromethane (CH2Cl2) A colorless, volatile liquid with an odor of ether. Boils at 40.1°C (104.2°F); freezes at -97°C (- 143°F). Soluble in alcohol, ether; slightly soluble in water. Nonflammable and nonexplosive in air. It is a carcinogen and narcotic; its TLV is 100 ppm in air. Derived from the chlorination of methyl chloride, followed by distillation. Used as a refrigerant; in nonflammable paint removers; in plastics processing and solvent extraction; as a blowing agent in foams and an aerosol propellant; in solvent degreasing; and as a solvent in organic synthesis. Also called methylene dichloride, methylene chloride. Also called methylene chloride. dicyandiamide (NH2C(NH)(NHCN)) White crystals that are stable when dry. Soluble in liquid ammonia; partly soluble in hot water. Melts at 207 - 209°C ( 405 - 408°F). Not flammable. Derived from polymerization of cyanamide in the presence of bases. Used as a catalyst for epoxy resins, a stabilizer in detergents, a modifier in starch products, a thinner in oil-well drilling muds; in organic reactions, fertilizers, pharmaceuticals, dyestuffs, case-hardening preparations, soldering compounds; and many other uses. Also called cyanoguanidine. dielectric dissipation factor The ratio of the power dissipated in a dielectric to the product of the effective voltage and the current; or the cotangent of the dielectric phase angle; or the tangent of dielectric loss angle. Note: For plastics measured according to ASTM D150. Also called tan delta, permittivity loss factor, dissipation factor, dielectric loss tangent. dielectric loss tangent See dielectric dissipation factor. differential scanning calorimetry DSC is a technique in which the energy absorbed or produced is measured by monitoring the difference in energy input into the substance and a reference material as a function of temperature. Absorption of energy produces an endotherm; production of energy results in an exotherm. May be applied to processes involving an energy change, such as melting, crystallization, resin curing, and loss of solvents, or to processes involving a change in heat capacity, such as the glass transition.dimethyl ketone See acetone. direct contact hot tool welding A form of heated tool welding in which the thermoplastic parts are pressed directly against the hot tool or plate. Part surfaces are heated until the melting or glass transition is reached. The hot tool is then removed, and the parts are pressed together until cooled. The hot tool can be coated with polytetrafluoroethylene to reduce melt sticking. See also heated tool welding, hot tool welding. dissipation factor See dielectric dissipation factor. dissolving capacity See solubility. DMF See N,N-dimethylformamide. dodecanedioic acid hexamethylenediamine polymer See nylon 612. driving torque In mechanical fastening, the force necessary to drive a self-tapping screw into a pilot hole. Lower values are optimal. drop dart impact strength See falling weight impact energy. drop weight impact strength See falling weight impact energy. durability See stability. durometer hardness Indentation hardness of a material as determined by either the depth of an indentation made with an indentor under specified load or the indentor load required to produce a specified indentation depth. The tool used to measure indentation hardness of polymeric materials is called a durometer, e.g., Shore-type durometer. E EA rubber See ethylene acrylic rubber. EAR See ethylene acrylic rubber. ECTFE See ethylene chlorotrifluoroethylene copolymer. elasticity constant See modulus of elasticity. electrofusion welding A technique used for joining thermoplastic pipes or liners, in which electricity is applied to a heating element surrounded by a thermoplastic material. The heat produced causes the thermoplastic material and the thermoplastic on the surface of the pipes to melt and flow together, forming a weld. Commonly used for joining polyethylene pipes. electromagnetic radiation Waves of electric charges propagated through space by oscillating electromagnetic fields and associated energy. electromagnetic welding See induction welding. electron beam See electron beam radiation. electron beam radiation Ionizing radiation propagated by electrons that move forward in a narrow stream with approximately equal velocity. Also called electron beam. Elmendorf tear strength The resistance of flexible plastic film or sheeting to tear propagation. It is measured, according to ASTM D1922, as the average force, in grams, required to propagate tearing from a precut slit through a specified length, using an Elmendorf-type pendulum tester and 2 specimens, a rectangular type and one with a constant radius testing length. elongation The increase in gauge length of a specimen in tension, measured at or after the fracture, depending on the viscoelastic properties of the material. Note: Elongation is usually expressed as a percentage of the original gage length. Also called ultimate elongation, tensile elongation, breaking elongation. EMAC See ethylene methyl acrylate copolymer. embrittlement A condition of low ductility in metals resulting from chemical or physical damage. Also called metal embrittlement. energy director A triangular shaped bead of plastic that is molded into one of the parts to be joined. Used in ultrasonic welding, it concentrates ultrasonic energy at the point, resulting in rapid heat buildup and melting. environmental stress cracking Cracking or crazing that occurs in a thermoplastic material subjected to stress or strain in the presence of particular chemicals or weather conditions or as a result of aging. Also called ESC. EP See epoxy resin.
كلمة سر فك الضغط : books-world.net The Unzip Password : books-world.net أتمنى أن تستفيدوا من محتوى الموضوع وأن ينال إعجابكم رابط من موقع عالم الكتب لتنزيل كتاب Handbook of Plastics Joining - A Practical Guide رابط مباشر لتنزيل كتاب Handbook of Plastics Joining - A Practical Guide
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