Polyolefin elastomer

This TPE is used for handles on power and hand tools but also as grips on everything from pens to golf clubs. Manufacturers use two-shot mouldings to form these grips but sometimes adhesives are required for prototype parts or for supplementing 

All shear strengths are given as guidelines only and may vary considerably depending on grade of rubber, fillers, surface finish, etc. 

Thermoplastic elastomers can be quite difficult to adhesively bond (Table 4.11) and invariably a primer or some other form of surface treatment (see Section 6.3) is necessary. 

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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... 

If polypropylene is too hard for the purpose envisaged, then the user should consider, progressively, polyethylene, ethylene-vinyl acetate and plasticised PVC. If more rubberiness is required, then a vulcanising rubber such as natural rubber or SBR or a thermoplastic polyolefin elastomer may be considered. If the material requires to be rubbery and oil and/or heat resistant, vulcanising rubbers such as the polychloroprenes, nitrile rubbers, acrylic rubbers or hydrin rubbers or a thermoplastic elastomer such as a thermoplastic polyester elastomer, thermoplastic polyurethane elastomer or thermoplastic polyamide elastomer may be considered. Where it is important that the elastomer remain rubbery at very low temperatures, then NR, SBR, BR or TPO rubbers may be considered where oil resistance is not a consideration. If, however, oil resistance is important, a polypropylene oxide or hydrin rubber may be preferred. Where a wide temperature service range is paramount, a silicone rubber may be indicated. The selection of rubbery materials has been dealt with by the author elsewhere. ... 

The chassis is made from a 1/4 in. sheet of either ABS or TPO vacuum formed into a tub and reinforced with reinforced pultruded glass fiber-TS polyester plastic tubing. The hood and other products are being made from a 20 mm thick sandwich of thermo-formed PPO-alloy skins, glass fabric infused with thermosetting vinyl ester, and a urethane foam core. The bumper and front fascia is thermoformed from a polyolefin elastomer sheet with an UV-resistant cap layer of DuPont s Tediar PVF film. The dash and... 

New family of TPV having heat and oil resistance based on ACM and polyamide Development of crystalline-amorphous block copolymers (Engage), mettalocene catalyzed TPEs, Polyolefin elastomer (POEs), application research on TPEs Protein-based block-copolymer... 

In addition to the two-phase TPEs, two new technologies have emerged. They are the metallocene-catalyzed polyolefin plastomers (POPs, the name given to Exxon s EXACT product line) and polyolefin elastomers (POEs, DuPont Dow Elastomer s ENGAGE), and reactor-made thermoplastic polyolefin elastomers (R-TPOs). These new types of TPEs are often called metallocene elastomers-TPEs (MEs-TPEs) [87]. The new POPs and POEs are essentially very low-molecular-weight-Unear low-density PEs (VLMW-LLDPE). These new-generation TPEs exhibit mbber-like properties and can be processed on... 

ABS or ASA (acrylonitrile-styrene-acrylate) Carboxylated polyolefin elastomer (SEBS-MA)... 

Obviously, there exists severe interplastics competition, e.g. PP vs. ABS, clarified PP vs. PS, PA, PVC, HDPE and PS (Table 10.7). A wide range of cross-linked and thermoplastic elastomer applications, from footware to automotive parts and toothbrushes, are adopting new metallocene-catalysed polyolefin elastomers (POEs). These low-density copolymers of ethylene and octene were first accepted as impact modifiers for TPOs, but now displace EPDM, (foamed) EVA, flexible PVC, and olefinic thermoplastic vulcanisates (TPVs). Interpolymer competition may also result from... 

Eaves (92) distinguished between polyolefin plastomers (POP) with density >910 kg m and polyolefin (POE) elastomers with densities <910 kg m-3. The density of a polyethylene at 20 °C is a linear function of the crystallinity, with limiting values of 854 kg m 2 for zero crystallinity and 1000 kg m for 100% crystallinity. The polyolefin elastomer foams compete with EVA copolymer foams. Metallocene chemistry also allows the production of copolymers with a larger comonomer content in the high molecular weight part than in the low molecular weight part this... 

No.4, July 2001, p.333-52 INVESTIGATION OF THE RADIATION CROSSLINKED FOAMS PRODUCED FROM METALLOCENE POLYOLEFIN ELASTOMERS/ POLYETHYLENE BLEND Kim D W Kim K S... 

RECYCLING TECHNOLOGY FOR LAMINATES COMPOSED OF THERMOPLASTIC POLYOLEFIN ELASTOMER AND CROSSLINKED POLYPROPYLENE FOAM... 

They are able to polymerize a large variety of vinyl monomers. The polymer microstructure can be controlled by the symmetry of the catalyst precursor. Prochiral alkenes such as propylene can be polymerized to give stereospecific polymers,554 572-574 allowing production of polyolefin elastomers. They can give polyolefins with regularly distributed short- and long-chain branches which are new materials for new applications. 

Baldwin, F.P., VerStrate,G. Polyolefin elastomers based on ethylene and propylene. Rubber Chem. Techn. 45,709-881 (1972). 

Guo, Z., Fang, Z., and Tong, L. 2007. Application of percolation model on the brittle to ductile transition for polystyrene and polyolefin elastomer blends. eXPRESS Polymer Letters 1 37-43. http //www. expresspolymlett.com/... 

Butyl rubber is one of the older synthetic rubbers, having been developed in 1937. Because of the saturated nature of a polyolefin elastomer, the commercial polymer is actually a copolymer of isobutylene and isoprene. The isoprene is added to provide cure sites. In addition, halogenated (bromo or chloro) derivatives are available. 

Within the family of polyolefins there are many individual families that include low density polyethylenes, linear low density polyethylenes, very low polyethylenes, ultra low polyethylenes, high molecular weight polyethylenes, ultra high molecular weight polyethylenes, polyethylene terephthalates, ethylene-vinyl acetate polyethylenes, chlorinated polyethylenes, crosslinked polyethylenes, polypropylenes, polybutylenes, polyisobutylene, ionomers, polymethylpentene, thermoplastic polyolefin elastomers (polyolefin elastomers, TP), and many others. 

Antioxidant used for wood or other natural fiber filled polyolefins, elastomers and hot melt adhesives when light exposure and maintenance of color is important. 

Ho, T. Martin, J. M. Structure, Properties and Applications of Polyolefin Elastomers Produced by Constrained Geometry Catalysts. In Metallocene-based Polyolefins Preparation, Properties and Technology, Scheirs, J., Kaminsky, W., Eds. Wiley Chichester, 2000 Vol. 2 175. 

Figure 1.44 Micrographs of asphalt-polyolefin elastomer (POE) blend obtained with transmitted light microscopy (a) bright-field image that cannot reveal the two phases in the blend and (b) a fluorescence-labeled image that reveals two-phase morphology. (Reproduced with permission of Jingshen Wu.)...

Lu, H.L. Hong, S. Chung, T.C. Synthesis of new polyolefin elastomers, poly(ethylene-ter-propylene-ter-p-methylstyrene) and poly(ethylene-ter-l-octene-ter-p-methylstyrene). Macromolecules 1998, 31, 2028. 

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