Elastomers processing

Elastomeric state Elastomer modifiers Elastomer process Elastomers... 

A typical elastomer selection for service in the oil field environment is often based on what might logically be described as the best of a bad lot in the selection process. Elastomers based on addition polymerization reactions,i.e., NBR, FKM, CR, EPDM are more... 

Raw-gum fluorocarbon elastomers are transparent to translucent with molecular weights from approximately 5000 (e.g., VITON LM with waxy consistency) to over 200,000. The most common range of molecular weights for commercial products is 100,000 to 200,000. Polymers with molecular weights over 200,000 (e.g., Kel-F products) are very tough and difficult to process. Elastomers prepared with vinylidene fluoride as comonomer are soluble in certain ketones and esters, copolymers of IFF and propylene in halogenated solvents perfluorinated elastomers are practically insoluble.16... 

Parasiewicz, W. Analysis of chemical hazards in the rubber manufacturing process. Elastomers 5(1), 17-28 (2001). in Polish... 

The thermoplastic polyesters have been often blended with amorphous polymers to improve chemical resistance and processability. Elastomers have also been added to improve their impact resistance. 

Alcryn A trade name for DuPont s fanuly of melt-processable elastomers and rubbers. 

Polyurethanes continue to be one of the most versatile of all polymers, finding applications in foams (flexible, rigid, and in-between), elastomers, coatings, sealants, adhesives, paints, textiles, and films. This volume presents some of the major advances in polyurethanes, both from the materials and research side of things as well as processing and applications, and includes studies on foams (additives, vacuum panel applications, blowing and processing), elastomers, adhesion behaviour and new urethane raw materials. 

The dynamically vulcanized blends are melt-processable elastomers, which can be processed by conventional injection molding, blow molding, and extrusion techniques. Some key factors affecting the performance of a TPV are... 

Keywords blends, processing, elastomer modification, d)mamic vulcanization, morphology, injection molding, extrusion molding, thermoplastic elastomer, thermoplastic dynamic vulcanizates (TDV), application. 

Tackifiers (A.S.C., 1986 Dick, 1987) - Tackifiers are used in certain types of adhesives and sealants to greatly improve initial adhesive strength (tack strength) on contact with an adherend surface before a stronger bond is formed later during the cure process. Elastomers such as natural rubber and butyl rubber, and thermoplastic hot melt systems all have low tack and require tackifiers to adhere well to polar substrates such as glass, ceramics, masonry and metal surfaces. 

The ability, or inability, of a resin to react under certain conditions is an important property. Many resins, such as polyethylene, are relatively unreactive and are used primarily for the physical properties they impart to the finished product. Other resins are synthesized with reactive sites so that they can be made to react further. Ion exchange resins fall into this category so do the polymeric components of reactive coatings, and adhesives, and reactively processed elastomers and plastics. 

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