Strength thermoplastic

Plastic Materials In comparison with metalhc materials, the use of plastics is limited to relatively moderate temperatures and pressures [230°C (450°F) is considered high for plastics]. Plastics are also less resistant to mechanical abuse and have nigh expansion rates, low strengths (thermoplastics), and onlv fair resistance to solvents. However, they are lightweight, are good thermal and elec trical insiilators, are easy to fabricate and install, and have low fric tion factors. 

High impact strength thermoplastic resins can be prepared by mixing a styrene/acrylonitrile copolymer with rubber particles. In general, the styrene/acrylonitrile copolymer is prepared by the graft copolymerization of styrene and acrylonitrile in the presence of rubber itself (17). 

The high impact strength thermoplastic resin exhibits different characteristics. According to the rubber used in the composition, the properties of the final product can be tailored to some extent. 

Bulk Properties. Block polymers can show mechanical properties in the bulk state that are superior to those that can be achieved with the corresponding homopolymers or random copolymers. This improvement in behavior is made possible by the segregated phase structure in block polymers. Of primary interest have been structures possessing both soft and hard phases. These polymers may range from the thermoplastic elastomers in which the hard phase is dispersed in a soft phase matrix, to toughened (i.e., high impact strength) thermoplastics in which the soft phase is dispersed in a... 

Polyblends, also in most cases as high-impact-strength thermoplastics. The soft phase is an elastomer or semicrystalline thermoplastic with a low glass transition temperature Tg... 

Homogenous blends of a thermoplast and an elastomer, or two thermoplasts, are produced to plasticize the matrix. On the other hand, heterogenous blends of elastomer particles in a continuous thermplast phase may produce high-impact-strength thermoplasts. Addition of fibers to thermoplasts increases rigidity. Blends can, however, be produced for a variety of other reasons to make polymers more flameproof with additive materials, to make processing easier, etc. 

High-impact-strength thermoplastics always consist of a hard and a pliable component. The two components may be chemically or physically different. In partially crystalline polymers, the hard component is the crystalline component and the pliable component is the amorphous component. On the other hand, the hard component may be a material with a higher glass-transition temperature and the pliable component may be a rubber [for example, poly(styrene)-poly(butadiene)]. The two incompatible... 

These are temperature-resistant thermoplastic adhesives which require fairly high temperatures for heat activation after solvents have been removed. Polysulfones are a family of tough, high-strength thermoplastics which... 

BeU, J.J. and W.J. Robertson, Hot melt bonding with high strength thermoplastic rubber polymers, presented at S AE Automotive Engineering Congress Exposition, Detroit, MI, February 25-March 1,1974, SAE Paper No. 740261. 

High-strength thermoplastic United States 4,097,550 1978 General Electric... 

Rubbers with improved modulus and tensile strength Thermoplastic polyolefin elastomers W. Germany 2,646,480 1977 Mitsui Petrochemical... 

Curgul, S., YilgOr, L, Yilgor, E., Erman, B., Cakmak, M. (2004), Effect of chemical composition on large deformation mechanooptical properties of high strength thermoplastic poly(urethane urea)s, Macmmolecules, 16,8676-85. 

The development of high strength thermoplastic adhesive copolymers of the EAA type containing reactive carboxyl groups has made it practical to bond insulation such as polyethylene to metal conductors to provide adequate bonding and long term environmental resistance. Frequently, the EAA copolymer is extruded around the cable. Peacock reports that when a layer of acrylic acid-ethylene copolymer (7 43) was extruded at 140°C over a flexible aluminum conductor followed by a layer of polyethylene insulation, the bond strength between the insulation and the conductor was 72 N/cm compared with 1.4 N/cm for a control assembly without the copolymer adhesive. There are numerous similar patent claims for insulated conductor cable. 

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