Copolymers adhesion between elastomers

Nature of the Interface. The most important aspect is the nature of the matrix-dispersed phase interface which determines the adhesion between these two phases. The anchoring effect between two phases with a block copolymer located at the interface depends essentially on the amount of Cop in the blend, the amount of elastomer, and the particle size of the dispersed phase. Particle size, in turn, depends on the molecular characteristics of homopolymer and Cop, as well as on the composition of the blend. In order to take into account these... 

They have made contributions on fluoropolymers especially on high-temperature and low-temperature adhesives and elastomers. One interesting copolymer is ethylene and tetrafluoroethylene (1 1), which is emulsion polymerized in the presence of a persulfate catalyst. This copolymer, unlike PTPE, is radiation-resistant. Another fluoropolymer project is the copolymerization between tetrafluoroethylene and hexafluoropropene. One high-... 

Di-block (A-B) and tri-block (A-B-A) copolymers are made by so-called living polymerization (section 1.7). These polymers have found applications as thermoplastic elastomers and as compatibilizers to increase the adhesion between the phases in polymer blends. 

It is known that most mixtures of elastomers and resinous copolymers are rather polydisperse, their incompatibility giving rise to poor interfacial adhesion. Preferably, a resinous monomer or monomers are grafted to the rubber, and they act as a link between the rubber and the resin phases. As Rosen (13) has pointed out, one means of predicting the affinities of polymer pairs from measurable properties is through the use of the solubility parameter, and this has proved useful in this study. The solubility parameter concept was originally derived from the thermody-... 

In the early 1950 s, B.F. Goodrich introduced the first commercial elastomer based on ionic interactions, a poly(butadiene-co-acry-lon1trile-co-acrylic acid). Typically less than 6% of carboxylic monomer 1s employed in order to preserve the elastomeric properties inherent in these systems. When neutralized to the zinc salt, these elastomers display enhanced tensile properties and improved adhesion compared to conventional copolymers. This enhancement of properties can be directly attributed to ionic associations between the metal carboxylate groups. 

Ticona Hostaform acetal copolymer was overmolded with styrene-ethylene/butylene-styrene (SEES) thermoplastic elastomer (TPE), which had an adhesive strength at the interface between polyacetal and TPE better than the tear strength of the TPE [10]. 

Block copol3nners form a new class of molecular composite materials by the phase separation of incompatible hard and soft segments which form their macro-molecular structure. Thermoplastic elastomers where the soft segments form the continuous phase have been extensively investigated by means of an adsorption-interdiffusion (A-I) model for the interfacial phase which bonds the hard and soft phases. The molecular structure and rheological activity of the interfacial phase in thermoplastic elastomer block copolymers is shown to play a dominant role in nonlinear viscoelastic response, mechanical hysteresis and energy absorption. Creation of elastomeric microphases in epoxy structural adhesives has been recently identified with in situ block copol3nnerization between carboxy terminated nitrile (CTBN) rubber and the diepoxide. 

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