Thermoplastic copolymers

Uses. Vinyhdene fluoride is used for the manufacture of PVDF and for copolymerization with many fluorinated monomers. One commercially significant use is the manufacture of high performance fluoroelastomers that include copolymers of VDF with hexafluoropropylene (HFP) (62) or chlorotrifluoroethylene (CTFE) (63) and terpolymers with HEP and tetrafluoroethylene (TEE) (64) (see Elastomers, synthetic-fluorocarbon elastomers). There is intense commercial interest in thermoplastic copolymers of VDE with HEP (65,66), CTEE (67), or TEE (68). Less common are copolymers with trifluoroethene (69), 3,3,3-trifluoro-2-trifluoromethylpropene (70), or hexafluoroacetone (71). Thermoplastic terpolymers of VDE, HEP, and TEE are also of interest as coatings and film. A thermoplastic elastomer that has an elastomeric VDE copolymer chain as backbone and a grafted PVDE side chain has been developed (72). 

Using this equation, the approximate (T — T ) value required for a film of a thermoplastic copolymer to be dry-to-touch, ie, to have a viscosity of 10 mPa-s(=cP), can be estimated (3,4). The calculated (T — T ) for this viscosity is 54°C, which, for a film to be dry-to-touch at 25°C, corresponds to a T value of —29 "C. The calculated T necessary for block resistance at 1.4 kg/cm for two seconds and 25°C, ie, rj = 10 ° mPa(=cP), is 4°C. Because the universal constants in the WLF equation are only approximations, the T values are estimates of the T requited. However, if parameters such as the mass per area appHed for blocking were larger, the time longer, or the test temperature higher, the T of the coating would also have to be higher. 

Figure 1. Relationship between (normalized) tensile strength and HPL content of injection molded blends with ethylene vinyl acetate copolymer. (Vinyl acetate content of the thermoplastic copolymer is given in parentheses.) (Strength values expressed in percent of unblended copolymer.) (From Ref. 11, with permission by Marcel Dekker, Inc.)...

The term ionomer was originally introduced in 1964 by Dupont to indicate a thermoplastic polymer containing both covalent and ionic bonds (5-7). By definition, ionomers are statistical thermoplastic copolymers consisting of (8) ... 

STYRENE-MALEIC ANHYDRIDE. A thermoplastic copolymer made by the copolymerization of styrene and maleic anhydride. Two types of polymers are available—impact-modified SMA terpolymer alloys (Cadon ) and SMA copolymers, with and without rubber impact modifiers (Dylark ). These products are distinguished by higher heat resistance than the parent styrenic and ABS families. The MA functionality also provides improved adhesion to glass fiber reinforcement systems. Recent developments include lerpolymer alloy systems with high-speed impact performance and low-temperature ductile fail characteristics required by automotive instrument panel usage. 

For polystyrene and related thermoplastic copolymers, this inherent brittleness has been corrected effectively by including rubbery particles, properly modified by grafting with thermoplastic chains, for energy dissipation (6). With crosslinked epoxy resins, chemical attachment of the... 

Elastomeric polyether-ester block copolymers were prepared by melt transesterification of poly(tetramethylene ether) glycol of molecular weight approximately 1000 with a variety of diols and esters. The ease of synthesis and the properties of these thermoplastic copolymers have been related to the chemical structure and concentration of the ester hard segments. 

Ethylene propylene copolymers and their blends exhibit diverse degradation behavior under the influence of light, heat and radiation. In spite of many papers in this area, little, if any, mechanistic data on degradation and stabilization of this important class of materials is available in the literature. The present paper reviews the published literature in this area organised under five distinct class of materials, namely, thermoplastic, elastomeric, and heterophasic copolymers, thermoplastic elastomer and blends. Of this, elastomeric ethylene-propylene copolymers appears to have been most exhaustively studied. Very few studies have reported on thermoplastic copolymers, both random as well as heterophasic as well as thermoplastic elastomers and blends. Specific mechanisms of degradation and stabilization of each of these classes of materials are discussed. 

Membrane Fabrication, Lamination and Reinforcement. The thermoplastic copolymer of TFE and PVEX monomer can be extruded or molded into a thin film by conventional methods. Extrusion is most appropriate for continuous production of large membranes because it facilitates control of film thickness. Lamination can be performed with a roll press to obtain multilayer membrane. To improve their mechanical properties, membranes are generally reinforced with an inert material such as fabric made of PTFE (67, 68), fibriled PTFE (69), or wire netting (70). 

During the past four years, linear low-density polyethylene (LLDPE) has probably become the most important of the thermoplastic copolymers. In contrast to the customary practice of producing branched ethylene homopolymer in a high-pressure reaction, a system of copolymerizing ethylene with a-C g olefins at low pressure is used to make LLPDE copolymer. This random copolymerization is commercially carried out in gas-phase, slurry, and solution processes in the presence of a transition metal catalyst 1-butene, 1-hexene, 4-methyl-l-pentene, or 1-octene are choices of comonomer. In the face of plant overcapacity and idle equipment existing at this time, LLDPE can also be made in high-pressure autoclaves and tubular reactors. 

Vinylidene Fluoride Hexafluoropropylene Copolymer - Thermoplastic copolymer of vinylidene fluoride and hexafluoropropylene. Has better thermal stability, antistick, dielectric, and antifriction properties, and chemical resistance, but lower mechanical strength at room temperature and creep resistance, compared to incompletely fluorinated fluoropolymers. Processing by conventional thermoplastic techniques is difficult due to its high melt viscosity. Uses include chemical apparatus, containers, films, and coatings. Also called TAM... 

Shalaby, S. W., Thermoplastic copolymers, in Thermal Characterization of Polymeric Materials, Turi, E. A., Ed., Academic Press, New York, 1981, chap. 3. 

Fluoriuated Ethylene Propylene Copolymer Thermoplastic copolymer of tetrafluoroethylene and hexafiuoro-propylene. Has deereased tensile strength and wear and creep resistanee, but good weatherability, dielectric properties, fire and ehemical resistance, and friction. Decomposes above 204°C (400°F), releasing toxic products. Processed by molding, extrusion, and powder coating. Used in chemieal apparatus liners, pipes, containers, bearings, films, eoatings, and cables. Also called FEP. 

Styrene Maleic Anhydride Copolymer Thermoplastic copolymer of styrene with maleic anhydride. Has good thermal stability and adhesion, but decreased chemical and light resistance. Processed by injection and foam molding and extrusion. Used in auto parts, appliances, door panels, pumps, and business machines. Also called SMA. 

Definition Thermoplastic copolymer of ethylene and vinyl acetate monomers... 

Dotation High m.w. thermoplastic copolymer of bisphenol A and ep-ichlorohydrin Emfxrical (C,H 0,) ... 

Styrene/butadiene polymer Copernica cerefera wax Copernicia cerifera wax. See Carnauba (Copernica cerifera) wax Copherol 1250. See d-a-Tocopheryl acetate Copherol F-1300. See D-a-Tocopherol Copisil . See Bentonite Copo 1500 Copo 1502 Copo 1505 Copo 1507 Copo 1712C Copo 1721. See Styrene/butadiene polymer Copolyester elastomer thermoplastic Copolyester, thermoplastic elastomer. See Polyester elastomer, thermoplastic Copolymer 186 Copolymer 186-85. See Castor oil, dehydrated... 

No-flow, fluxing type underfill Novolac and Bisphenol-F epoxy resins 40-50% Methyl hexahydrophthalic anhydride 20-30% Polysebacic and proprietary anhydride mixture 7-12% Thermoplastic copolymer Amicon El 350, 1355... 

Polysulfone is a thermoplastic copolymer of the sodium salt of bis-phenol A and p,/7 -dichlorodiphenyl sulfone ... 

AMMA Thermoplastic copolymer from acrylonitrile and methyl... 

Elastomeric silicones with methyl substituents Methylstyrene-styrene-acrylonitrile-grafted polybutadiene Thermoplastic copolymer from a-methyl styrene and acrylonitrile... 

Copolymer from styrene and butadiene (also SB, S/B) Thermoplastic copolymer from styrene and acrylonitrile, also SAN... 

SAN Thermoplastic copolymer from styrene and acrylonitrile, also... 

A thermoplastic copolymer made from ethylene and vinyl acetate. This copolymer is similar to polyethylene but has considerably increased flexibility. 

A thermoplastic copolymer of st5rcne and acrylonitrile. If it comprises either SAN-grafted butadiene or is blended with nitrile rubber, NBR, a terpolymer is known as ABS. 

Philprene Styrene-butadiene thermoplastic copolymer, SBR Phillips 66 Co. 

---