tailieunhanh - Materials Selection Deskbook 2011 Part 11

Tham khảo tài liệu 'materials selection deskbook 2011 part 11', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Properties and Selection of Materials 137 Plasticizer Material added to a plastic to increase its workability and flexibility. Plasticizers tend to lower the melt viscosity the glass transition temperature and or the elastic modulus. Plastisol Polyamide plastics Polyester plastics Suspension of finely divided resin in a plasticizer. See nylon plastics. Group of plastics composed of resins derived principally from polymeric esters that have recurring polyester groups in the main polymer chain. These polyester groups are crosslinked by carbon carbon bonds. Polyethylene Plastic or resin made by the polymerization of ethylene as the sole monomer. Polymer Material produced by the reaction of relatively simple molecules with functional groups that allow their combination to proceed to high-molecular weights under suitable conditions formed by polymerization or polycondensation. Polymerization Chemical reaction that takes place when a resin is activated. Polypropylene Plastic or resin derived from the polymerization of propylene as the principal monomer. Polystyrene Plastic derived from a resin produced by the polymerization of styrene. Polyvinyl acetate Resin derived from the polymerization of vinyl acetate. Polyvinyl alcohol Polymer derived from the hydrolysis of polyvinyl esters. Polyvinyl chloride Resin derived from the polymerization of vinyl chloride. Polyvinyl chlorideacetate Pot life Copolymer of vinyl chloride and vinyl acetate. Time period beginning once the resin is catalyzed and terminating when material is no longer workable working life. Preform Coherent block of granular plastic molding compound or of fibrous mixture with or without resin. Prepared by sufficiently compressing material forming a block that can be handled readily. 138 Materials Selection Deskbook Prepolymer An intermediate chemical structure between that of a monomer and the final resin. Pressure tubing Tubing used to convey fluids at elevated temperatures and or pressures. Suitable for head