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Prof. Dr. Abdullah Khan Durrani. Polymers Abbreviations. POLYMERS. Categories of Polymers. THERMOPLASTICS. THERMOSETS. ELASTOMERS. Thermoplastics. Acetals. polyesters. acrylics. polyethylenes. abs. polyimides. cellulosics. polypropylenes. fluorocarbons. polystyrenes. polyamides.
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POLYMERS Categories of Polymers THERMOPLASTICS THERMOSETS ELASTOMERS
Thermoplastics Acetals polyesters acrylics polyethylenes abs polyimides cellulosics polypropylenes fluorocarbons polystyrenes polyamides polysulfones polycarbonates Polyvinyl chloride
Thermosets alkyds phenolics aminos polyesters urea polyimides epoxies silicones
ELASTOMERS rubbers silicones polyurethane
Plastics 1- On behalf of processing 2-On behalf of Mechanical Properties 3- On behalf of other Properties
Additives Additives (also known as modifiers) are substances added to a material usually to improve its properties, but they can also be used as extenders to reduce cost. Although some additives provide a broad use and are applicable to many plastics, others may be used exclusively for only one or two plastics; for example plasticizers are generally developed for specific plastics.
Additives were originally used in plastic compounding to overcome limitations of the base resin. For example, they provided more effective flame resistance or improved flexibility. Gradually, the uses of additives and modifiers were extended to provide advantages in processing of the materials (e.g., lubricants and slip agents).More recently, the uses of additives and modifiers have been extended even further to provide completely new types of materials with properties much different from those of the base resin. Examples of this are blowing agents that can be used to pro-duce foamed plastic products and adhesion promoters that can be used to improve adhesion to internal reinforcement materials.
plastic additives are generally classified by their function rather than by chemistry. The following is just a short list of additives based on the functions they can provide in polymeric formulations: adhesion promoters, antiblocking agents, antifogging agents, antioxidants, antistatic agents, biocides, blowing agents, coupling agents, de foamers (or air release agents), flame retardants, heat stabilizers, impact modifiers, low-profile additives, lubricants, plasticizers, slip agents, thickeners, UV stabilizers, and wetting agents.