Plastics Craftech Industries, 2013 Engineering 8 Dock Street, Hudson, NY 12534 Website: www.craftechind.com Dictionary of Manufacturing Terms Blog: info.craftechind.com/blog E-mail: [email protected] Phone: 518-828-5001 or 800-833-5130 Fax: 518-828-9468 ABS See Acrylonitrile butadiene styrene. Abrasion resistance is the ability of a material to tolerate mechanical action by means of friction such as rubbing, scrapping etc. and helps maintain the original appearance of the part. Acetal forms when the hydroxyl group is lost as water. The ion that is produced is then rapidly attacked by a molecule of alcohol. Loss of the proton from the attached alcohol creates the acetal. Alkynes in organic chemistry are an unsaturated hydrocarbon containing one Acrylonitrile butsdiene styrene (ABS) carbon-carbon triple bond between two atoms. is a common thermoplastic polymer. Its glass Like other hydrocarbons, alkynes are generally transition temperature is approximately 105°C hydrophobic (see hydrophobic) but tend to be (221°F). ABS is amorphous and therefore has no more reactive. true melting point. ABS is a terpolymer, made by polymerizing styrene and acrylonitrile in the Aliphatic hydrocarbons are made up of presence of polybutadiene. carbon and hydrogen atoms joined together in straight chains, branched chains or nonaromatic Adhesive strength refers to the ability of rings such as white spirits and kerosene. an adhesive to adhere to a surface or bond two surfaces together. Amide groups are made up of a carbonyl group linked to a nitrogen atom. Amorphous Addition polymers involve the reaction of polymers’ molecular structure lacks a definite unsaturated monomers. Types of condensation repeating form. They have a glass transition polymers include polyamides, polyacetals and temperature but no definite melting point. polyesters. Amorphous Polymers have a molecular Additives include reinforcing fillers, like structure that lacks a continuous repeating form. fiberglass for strength, fillers added to create They have a glass transition temperature but no volume, plasticizers, flame retardants, colorants, definite melting point. UV resistance and many others. Most plastics are compounded from a resin and one or many Annealing is the process of heating a plastic additives. (See Craftech Industries Blog 10/27/14) gradually to above its glass transition point, maintaining that temperature for a specific Alkaline means having a pH greater than 7 and period of time and then allowing it to cool to a relatively low concentration of hydrogen ions. relieve internal stresses caused by manufacturing processes. Antioxidants are molecules that inhibit other molecules from being oxidized. 2 COPYRIGHT©2016 CRAFTECH INDUSTRIES Antistatic Agents are compounds used Birefringent is the optical property of an to treat materials or their surfaces to reduce or anisotropic material whose refractive index eliminate the buildup of static. depends on the polarization and propagation direction of light. Aromatic Hydrocarbons have alternating double and single bonds between carbon Bond Strength is the degree to which atoms atoms that form rings found in petroleum. The linked together in a chemical bond contribute to configuration of six carbon atoms in aromatic one another’s valency. compounds is called the benzene ring. The term Bronsted - Lowry Acids - Bases The basic “aromatic” is derived from the sweet scent many of concept of this theory is that when an acid and these compounds have. a base react with each other, the acid forms its Arrhenius Acids are substances that when conjugate base and the base forms its conjugate added to water increases the concentration of H1+ acid by exchange of a proton (the hydrogen ions present. An example would be HCL. cation, or H+). Arrhenius Bases are substances that when CAD/CAM System is the acronym for added to water increases the concentration of computer-aided design/computer-aided OH1- ions present. NaOH is an example of an manufacturing systems. They are used to design Arrhenius base. and manufacture products. An engineer can use the system to both design a product and program the machine that makes the part. Capillary Action, sometimes called wicking or capillarity, is a manifestation of surface tension by which the portion of the surface of a liquid coming in contact with a solid is elevated or depressed, depending on the adhesive or cohesive properties of the material. A liquid may flow into narrow spaces without the assistance of gravity and indeed sometimes in opposition to it. An example would be a paintbrush in paint. Carbocation is an ion with at least one positively charged carbon atom, for example methanium CH+. Benzene Rings are hexagonal rings arrangement found in benzene and other aromatic Charpy Impact Test or Charpy-notch test compounds, consisting of six carbon atoms with is a test that determines the amount of energy alternating single and double bonds between absorbed by a substance during fracture. The them, and with each carbon atom bonded to a energy absorbed is a measure of the material’s hydrogen atom, or to other atoms or groups of notch toughness. The Charpy impact test involves atoms in derivatives of benzene. striking a standard notched specimen with a controlled weight pendulum swung from a specific height. 3 COPYRIGHT©2016 CRAFTECH INDUSTRIES Chlorinated Polyvinyl Chloride (CPVC) Crazing refers to small hair-like cracks on the is a thermoplastic produced by the chlorination of surface of a plastic part. polyvinyl chloride (PVC) resin. Creep is the tendency of a solid material Coefficient of Linear Thermal to stretch or deform permanently under the Expansion (CLTE) is the relationship between influence of an unchanging load. a material’s dimensional response to heating and Cryogenics is the study of the production and cooling. behavior of materials at very low temperatures Comparative Tracking Index (CTI) that are generally accepted to be -150°C (-238°F). measures the electrical breakdown on the surface NIST has chosen to define cryogenics as below of an insulating material. It is often used to assess -180°C (-292°F). the electrical safety of an apparatus. Compressive strength is the ability of a material to resist a compressive force and is the force per unit area that it can withstand. ASTM D695 is the standard test method used in the United States. Condensation Polymers are any kind of polymer formed through a condensation reaction. With a condensation polymer, molecules join together and lose small molecules such as water or methanol. Conductive Plastics are hybrid polymers that Crystalline polymers have a regular and are electrically conductive or static dissipative. defined pattern to their molecular structure. These plastics are engineered to have specific They have a melting temperature but not a glass conductivity characteristics using additives such as transition temperature. Polymers with regular copper, silver, aluminum, carbon black, and carbon chain structures (e.g. isotactic) are the most likely fibers. to form crystalline regions. The more crystalline a polymer is, the stronger and less flexible it Conductivity is the measure of how easily an becomes. electric charge or heat can pass through a material. Cut-off burs are a projection of material left Continuous Service Temperature is the when the work piece falls from the stock before maximum temperature at which a material can the edge has been broken. perform reliably in a long term application. CPVC See Chlorinated Polyvinyl Chloride. Copolymers are polymers of two or more different monomers. Deflection is the displacement of a material under load. It is expressed in inches or millimeters. Copolymerization is a process in which unlike molecules join together in random sequences Density is defined as the mass per unit volume or alternating sequences. An example of or ρ = m/v copolymerization is ABS plastic. 4 COPYRIGHT©2016 CRAFTECH INDUSTRIES Dielectric Constant is the relative permittivity Electromagnetic interference (EMI) is an of a dielectric material. electromagnetic energy that causes interference in the operation of electronic equipment by Dielectric breakdown is the point at which disrupting electrical circuits. conducting paths begin to form in an insulating material allowing electrical current to flow. Electrostatic discharge (ESD) is a sudden flow of electricity between two points such as the Dies are a specialized tools used in discharge of static electricity to the ground. manufacturing to cut or shape material mostly using a press. Dies are generally customized to the Elastic is a colloquial term for certain kinds item they are used to create. of elastomers. Elastic materials are capable of recovering their size and shape after deformation. Die Cutting is the process of using a die to cut low-strength materials, such as plastics, Elasticity is the physical property of a polymer rubber, cloth, paper, corrugated fiberboard, and that allows it to return to its original state after paperboard. deformation. Elastomers are amorphous polymers existing above their glass transition temperature. At ambient temperatures, rubbers are thus relatively soft and deformable. Their primary uses are for seals, molded flexible parts, etc. Fisch is a thermo softening plastic. Flame Rating/UL 94 is an internationally accepted plastic flammability testing standard created by Underwriters Laboratories. V stands for vertical flame and HB for horizontal burn. Expressed as V-0, V-1, and V-2. V-0 is a vertical burn that stops within 10 seconds. V-1 is a vertical burn that stops in 30 seconds and V-2 is one in which Dielectric Strength is the maximum electrical the vertical specimen stops burning in 30 seconds field strength a material can withstand without with the allowance of drips of flaming particles. HB experiencing failure of its insulating properties. is the designation for horizontal slow burn. Dissipation Factor is the measurement Flame retardant materials are able to resist of how inefficient an insulating material is. It ignition when exposed to a flame or heat. measures the heat lost when an insulator such as a dielectric is exposed to an electrical field.