Elastomer modified thermoplastic

In the early stages of development of polypropylene rubbers, particularly butyl rubber, were used to reduce the brittleness of polypropylene. Their use declined for some years with the development of the polypropylene copolymers but interest was greatly renewed in the 1970s. This interest has been centred largely around the ethylene-propylene rubbers which are reasonably compatible in all proportions with polypropylene. At first the main interest was with blends in which the rubber content exceeded 50% of the blend and such materials have been designated as thermoplastic polyolefin elastomers (discussed in Section 11.9.1). There is also increasing interest in compounds with less than 50% rubber, often referred to as elastomer-modified thermoplastics. It is of interest to note... 

Such rubbery and thermoplastic polymers may be blended in any proportion, so that on one hand the product may be considered as a thermoplastic elastomer, and on the other as an elastomer-modified thermoplastic. There is, furthermore, a spectrum of intermediate materials, including those which might be considered as leather-like. In this area the distinction between rubber and plastics material becomes very blurred. 

ABS, an elastomer modified thermoplastic used in electrical and electronic equipment, house and office appliances and in the automotive industry) and redispersable powders for construction materials. Natural rubber accounted for 6.5 million tonnes per year, including about 1 million tonnes that is commercialized as a waterborne dispersion. 

If the rubber content of a PP blend is less than 50%, then the material may be referred to as rubber reinforced polypropylene (RRPP) or, as rubber modified polypropylene ( PP) or, as an elastomer modified thermoplastic MT) or, as an olefin thermoplastic elastomer (OTE) or, as impact modified polypropylene (IMPP). The material may also be known as a thermoplastic elastomer (TFE) or, as a thermoplastic rubber (TPR). The rubber/elastomer in such a mbcture is not crosslinked, or cured, or vulcanized). The term rubber reinforced PP (RMPP) will be used for those systems in which the rubber is present in relatively low concentations (<30%) and is not cross-linked/cured. 

Rubber modified polypropylene polypropylene/ethylene propylene rubber blends ethylene propylene rubber, polypropylene blends elastomer modified thermoplastic elastomer modified polypropylene impact modified polypropylene olefin thermoplastic elastomer thermoplastic polyolefc rubber. 

Blends of isobutylene polymers with thermoplastic resins are used for toughening these compounds. High density polyethylene and isotactic polypropylene are often modified with 5 to 30 wt % polyisobutylene. At higher elastomer concentration the blends of butyl-type polymers with polyolefins become more mbbery in nature, and these compositions are used as thermoplastic elastomers (98). In some cases, a halobutyl phase is cross-linked as it is dispersed in the polyolefin to produce a highly elastic compound that is processible in thermoplastic mol ding equipment (99) (see Elastomers, synthetic-thermoplastic). ... 

DuPont Acetal EVA Nylon 6, 6/6, 6/12, Mineral Filled 6/6, Industrial PBT PET Polyethylene Modified Thermoplastic Elastomer Ionomer Liquid Crystal Polymer ... 

Improve both impact strength and rigidity of thermoplastics by using up the energy of crack propagation. Elastomers are prototypical toughening additives. Examples of high-polymeric impact modifier/thermoplastic matrix systems are EVA, CPE and MBS in PVC, EP(D)M and SBS in PA, and acrylic rubbers in polyesters. 

Recent work has focused on a variety of thermoplastic elastomers and modified thermoplastic polyimides based on the aminopropyl end functionality present in suitably equilibrated polydimethylsiloxanes. Characteristic of these are the urea linked materials described in references 22-25. The chemistry is summarized in Scheme 7. A characteristic stress-strain curve and dynamic mechanical behavior for the urea linked systems in provided in Figures 3 and 4. It was of interest to note that the ultimate properties of the soluble, processible, urea linked copolymers were equivalent to some of the best silica reinforced, chemically crosslinked, silicone rubber... 

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. 

Chen et al. (12) showed that phase separation in elastomer-modified epoxies can also be detected with much more sensitivity using small-angle X-ray scattering (SAXS). Then, the choice of the cloud point as a criterion for detecting the beginning of phase separation can be discussed. We have not performed SAXS studies on our systems because phase separation is much faster in thermoplastic-modified epoxy and the scanning time is too long. 

Amoco Resin 18. [Amoco] Poly-a-methylstyrene extrusion and mending process aid in ABS, PVC, CPVC, and semirigid vinyl, thermoplastic urethanes, molded rubbers, and thermoplastic elastomers modifier and rein-forcer in adhesives, thermoplastic powd. coatings, hot-mielt coatings. 

Vandar . (Hoedist Cdanese/Et ineer-ing Plastics Hoechst UK] Thermoplastic alloy (elastomer-modified PBT), some glass or mineral filled used for automotive body conqxments and housings, furniture, ski boots, appliances, clips, fasteners. 

Various applications of the injection molding system have been developed outside the scope of the cure of rubbers, and a few examples are given, with the substitution of thermoset rubbers by thermoplastic elastomers a range of thermoplastic elastomer compounds were introduced and processed using reaction compounding technology. They are called reaction modified thermoplastic elastomers or ReMoTE [5]. 

Polyolefins A broad class of hydrocarbon-chain elastomers or thermoplastics usually prepared by addition (co)polymerization of alkenes such as ethylene. There are branehed and linear polyolefins and some are chemically or physically modified. Unmodified polyolefins have relatively low thermal stability and a nonporous, nonpolar surface with poor adhesive properties. Proeessed injection, blow, and rotational molding and extrusion. Polyolefins are used more and have more applications than any other polymers. Also called Olefinie Resins, Olefin Resins, and Polyolefin Resins. 

Acrylic resin Acrylonitrilefbutadiene/styrene copolymer Bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite Butadiene/acrylonitrile copolymer EthyleneA/A copolymer Methoxyethyl acrylate Methyl methacrylate butadiene styrene terpolymer Polyethylene elastomer, chlorinated 2-Propenoic acid, 2-methylmethyl ester, polymer with 1,3-butadiene and butyl 2-propenoate impact modifier, PVC rigid EVA/PVC graft polymer impact modifier, recycled polyamides EPDM, maleated impact modifier, thermoplastics Butadiene/acrylonitrile copolymer impact strength modifier PEG-6 trimethylolpropane impact-resistance lights Polyester carbonate resin impact-resistance, lights Polyester carbonate resin impeller... 

In an evaluation study on asphalts with modified bitumens, it was found that asphalt layers with thermoplastic polymer-modified bitumen, when laid over cracked and uncracked surfaces, have more intensive cracking within a very short period, in contrast to the asphalt layers where elastomer-modified bitumen was used (Anderson et al. 1999). 

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