Thermoplast rubber-modified

Woo et al. (1994) studied a DGEBA/DDS system with both polysul-fone and CTBN. The thermoplastic/rubber-modified epoxy showed a complex phase-in-phase morphology, with a continuous epoxy phase surrounding a discrete thermoplastic/epoxy phase domain. These discrete domains exhibited a phase-inverted morphology, consisting of a continuous thermoplastic and dispersed epoxy particles. The reactive rubber seemed to enhance the interfacial adhesive bonding between the thermoplastic and thermosetting domains. With 5 phr CTBN in addition to 20 phr polysul-fone, Glc of the ternary system showed a 300% improvement (700 Jm-2 compared with 230 J m 2 for the neat matrix). 

Thermoplastics may themselves be considered in four sub-classes (a) amorphous thermoplastics, (b) rubber-modified amorphous thermoplastics, (c) plasticised amorphous thermoplastics and (d) crystalline thermoplastics. 

Table 17 provides a list of various polysiloxane-poly(aryl ether) copolymers investigated. Depending on the type, nature and the level of the hard blocks incorporated, physical, thermal and mechanical properties of these materials can be varied over a very wide range from that of thermoplastic elastomers to rubber modified engineering thermoplastics. Resultant copolymers are processable by solution techniques and in some cases by melt processing 22,244). 

Report 86 High Performance Engineering Plastics, D.J. Kemmish, Victrex Ltd. Report 113 Rubber-Modified Thermoplastics, H. Keskkula, University of Texas at Austin. 

Report 113 Rubber-Modified Thermoplastics, H. Keskkula, University of Texas at Austin. 

The preferred morphology of these rubber modified amorphous thermoplastics is the distribution of distinct rubber particles unfilled or filled in an isotropic matrix of the basic polymer. This was shown to be the case for rubber modified polystyrene and for ABS-type polymers. 

Hourston, D. J., Lane, S. and Zhang, H. X., Toughened thermoplastics Part 2 impact properties and fracture mechanisms of rubber modified PBT, Polymer, 32, 2215-2220 (1991). 

Edwards, S. A. and Choudhury, N. R., Variations in Surface Gloss on Rubber-Modified Thermoplastics Relation to Morphological and Rheological Behavior, Polym. Eng. Set, 44, 96 (2004)... 

Tough matrices, such as thermoplastics and rubber-modified epoxies, are particularly useful for high fracture toughness and damage tolerance against... 

Other transitions such as degradation and phase separation may be also observed during the formation of the polymer network. Degradation is usually present when high temperatures are needed to get the maximum possible conversion. Phase separation may take place when the monomers are blended with a rubber or a thermoplastic, to generate rubber-modified or thermoplastic-modified polymer networks. In these cases, formulations are initially homogeneous but phase-separate during the polymerization reaction. This process is discussed in Chapter 8. 

M. C. O. Chang, On the Study of Surface Defects in the Injection Molding of Rubber-modified Thermoplastics, SPE ANTEC Tech. Papers, 40, 360-367 (1994). 

A comparatively new group of materials— thermoplastic elastomers or thermoplastic rubbers —combines the ease of processing of thermoplastics with qualities of traditional vulcanized rubbers, especially elasticity. Because of convenience in processing there is much interest too in blends of plastics with elastomers, which may be modified by the inclusion of filler or glass fibre. As an example, a rubber-like material that can be processed as a thermoplastic can be made by blending and melt-mixing an ethylene-propylene rubber with polypropylene. The use of such blends may be helpful when there are needs to reclaim and re-process material, and in order to obtain products with qualities intermediate between those of the main components of the blends. 

It is worth noting that this semi-ductile behavior has been found in other polymers Newmann and Williams [4] observed stable crack propagation before brittle fracture in ABS over the temperature range from —40 to 0°C Bernal and Frontini also observed this type of behavior in a rubber-modified thermoplastic at room temperature [12]. 

Use Automotive parts, gaskets, cable coating, mechanical rubber products, cover strips for tire side-walls, tire tubes, safety bumpers, coated fabrics, footwear, wire and cable coating, thermoplastic resin modifier. 

Much work has been reported on studying the structure of thermoset resins via SAXS, especially focussing on interpenetrating network polymers (IPNs), thermoset nanocomposites, rubber-modified thermosets and thermoset-thermoplastic blends. Most recently Guo et al, (2003) have examined the use of SAXS to monitor the nanostructure and crystalline phase structure of epoxy-poly(ethylene-ethylene oxide) thermoset-thermoplastic blends. This work proposes novel controlled crystallization due to nanoscale confinements. 

The importance of the science and engineering of toughened plastics is reflected in the successful series of symposia held on the topic under the auspices of the American Chemical Society. The first, on Rubber-Modified Thermoset Resins, was held in Washington, DC, in 1983 the papers from that conference were published in 1984 as Volume 208 of the Advances in Chemistry Series. The theme of the 1988 symposium, Rubber-Toughened Plastics, was broadened to cover both thermosets and thermoplastics. The papers from that symposium, held in New Orleans, LA, were published in 1989 as Volume 222 of the Advances in Chemistry Series. In 1990 the symposium returned to Washington, DC, and was titled Toughened Plastics Science and Engineering. The papers were published in 1993 as Volume 233 of the Advances in Chemistry Series. 

---