PA (polyamide) Polymer molecules which contain the repeated amide group -CO-NH- . Also called nylon. As an engineering plastic, PA is compounded with many kinds of additives to obtain improved properties.
Amorphous thermoplastic material based on terephthalic and isophthalic acids and bisphenol A in the polymer chains. It is a weather-resistant, semi-aromatic polyester.
A thermoplastic polyester created by polycondensation of butylene glycol with terephthalic acid or dimethyl terephthalate. Use of selected additives results in the engineering plastic PBT.
PC (polycarbonate) A thermoplastic, amorphous polymer where the repeated structural unit in the polymer chain is the carbonate group (-O-COO-). Applications include extremely impact resistant, transparent, protective and viewing windows and protective helmets.
PET (polyethylene terephthalate)
PET (polyethylene terephthalate) A polyester where the repeated structural unit in the polymer chain is the ester group (-COO-) interspersed with the benzene ring (-C6H4-) and ethyl (-CH 2 – CH 2-), made through polycondensation of terephthalic acid and ethylene glycol, it is used for the manufacture of polyester fibres and PET drink bottles.
A process of rendering a thermoplastic compound more processible by means of mechanical working and/or application of heat or, e.g. also by the addition of a plasticiser.
A material which contains a high polymer as an essential ingredient and which at some stage in its processing into finished or semi-finished products can be shaped by flow. Elastomeric materials which are also shaped by flow are not considered to be plastics.
PMMA (polymethyl methacrylate)
PMMA (polymethyl methacrylate, acrylic glazing material, Perspex) A transparent thermoplastic material with crystal clarity and brilliance. Due to its hardness and weatherability it is widely used in automotive construction. Brittleness is prevented by mixing with elastomers (with acrylonitrile as monomer). The chemical structure of PMMA the linear CH 2 chain has a methyl (CH3-)- and a methylester group (-COO-CH3 ) on every second position.
Polyacrylate (PAK). Polymer of an acrylic acid ester, a homologous or a substituted derivative of acrylic acids. A moulding material made up mainly of polyacrylates.
Polyamide 12 (PA 12 ) A thermoplastic polymer with 12 C-atoms in the monomer unit. It is manufactured through ring-opening polymerisation of laurolactam (13-link chain with an amide group) to form polymer chains and has the lowest water absorption capacity of all types of polyamides and thus the least change in properties due to environmental effects.
Polyamide 6 (polycaprolactam, PA 6, Nylon 6) A polyamide with 6 C-atoms in the monomer unit, manufactured from the ring-shaped caprolactam (7-link chain with an amide group) through ring-opening polymerisation to form polymer chains. With the addition of additives, PA 6 is a tough engineering plastic. It is used in barrier films and chemical fibres.
Polyamide 66 (PA 66, Nylon 66) PA 66 is manufactured through polycondensation of hexamethylene diamine (6 C-atoms) and adipic acid (6 C-atoms) with splitting-off of water. With the addition of additives, a tough engineering plastic is created which is used in automotive and electrical parts. PA 66 is also well known as a chemical fibre.
Polyblends (alloys) These are mixtures, often also called alloys, of different thermoplastic materials to create new plastic materials with previously unknown property profiles.
A thermoplastic material manufactured through the esterification of polyvalent alcohols and acids. They are used among other things as fibres, resins and paints (thermoplastic or thermosetting alkyd resin).
A family of soft, semi-crystalline, thermoplastic materials manufactured from ethylene (CH2 =CH2 ), with different structures: Branched macromolecules: PE-LD (low density) = high-pressure PE. Linear macromolecules: PE-HD (high density) = low pressure PE with higher cristalline content. A new metallocene catalysed PE is characterised by improved properties due to higher linearity. PE is a widely used bulk plastic material.
A thermoplastic, crystalline bulk plastic manufactured through the polymerisation of propylene. PP is widely used, inexpensive and has the greatest potential for growth. Copolymers and block-copolymers exist. The newly introduced isotactic and syndiotactic PP with regular molecular arrangement exhibit greatly improved properties and is produced in part with new metallocen catalysts.
PPS (polyphenylene sulfid)
A linear, high-crystalline thermoplast with S-bridges between the benzene rings in the chain. With branched types, a thermoset structure can be obtained through thermal post-treatement. When reinforced with glass fibres, PPS is heat resistant under long-term exposure to temperatures up to 240O C and is used in applications in the electrical and automotive industries.
A linear bulk thermoplastic material of amorphous character with atactically arranged benzene rings as side-additions to every second C-atom of the CH 2 – polymer chain. PS is transparent and relatively brittle. Many copolymers are derived from it, most well-known being PS foam. New, regularly formed PS structures form syndiotactic PS (=SPS) with higher crystallinity and a melt-temperature of 270OC.
Thermoplastische PUR elastomers (T-PUR) are re-meltable polymer structures with hard and soft segments between the urethane structures (-NH-COO-) which connect them in the molecule; made of dioles (-OH) and diisocyanates (-NCO). Multi-functional polyoles and tri-isocyanate or polyisocyanates are used as reactions partner for thermosetting PUR grades with high rubber elasticity. The soft segments may be polyether (-O-) for polyurethane or polyester (-COOO-) for polyester urethane. End products are ski boots, sport track coverings and soft and hard integral foams.
PVC (Polyvinyl chloride)
This thermoplastic bulk plastic has the monomer structural unit –CH2–CHCl in the polymer molecule and has exceptionally good long-term resistance as PVC-U (hard PVC) used as supply pipes. With the addition of plasticiser, PVC-P (earlier PVC-W) is relative soft and easy to process. Questions have been posed regarding possible environmental damage due to hydrochloric acid (HCl) formed when PVC is burnt.