Impact-resistant polymers

The tendency of polybutadiene to undergo chain transfer reactions can be used for the preparation of impact-resistance polymer where polystyrene has been grafted to polybutadiene as under ... 

New Transparent Impact-Resistant Polymer Blends from Resins and Rubbers Having Minimized Compositional Heterogeneities... 

Toughened polypropylene may be prepared by block copolymerization in which ethylene monomer is added during the final stages of the polymerization of propylene (4). Thus, some polypropylene chains would contain an end block of rubbery ethylene-propylene copolymer. Alternatively, a blend of an elastomeric copolymer of ethylene and propylene (EPR or EPDM) with isotactic polypropylene (PP) can produce an impact-resistant polymer (5). 

Impact-Resistant Polymers Polymers Modified with Rubbers... 

Glassy polymers, PMMA and PS, are suitable for many applications, but they are brittle when subjected to impact loads. The same things happens with thermoset polymers such as epoxy or phenolic resins. To solve this problem, impact-resistant polymers have been developed that basically consist of a matrix of the brittle polymer in which a second elastomeric... 

Study of impact-resistant polymer blends has elucidated the fundamental role of block and graft copolymers (Cop) in a typical system like PS-PI-Cop (I, 2) and also in the case of two-phase materials formed by two resins... 

R. P. Fellmann, W. H. Stass, and D. R. Kory, Impact-Resistant Polymer Mass, Ger. Offen. 2,748,751 (1978). Interpenetrating networks with poly(Me methacrylate). Co-continuous interpenetrating networks of chains. Ethylene vinyl acetate copolymer/poly(Me methacrylate) blends. 

EPDM and EPR are used to modify polyolefins, primarily in the automotive industry. The largest volume is in automotive PP bumpers. This application is gradually being replaced by impact-resistant polymers produced by metallocene technology, providing better performance and economics. DuPont Dow and Exxon are leading producers in North America. When used with plastics such as nylon, PET, and PBT, the EPDM and EPR are often modified with a functionalized monomer to allow them to react with the plastic. Additionally, the shell of a core-shell modifier can also be modified to include a reactive group. Suppliers of fimctionalized modifiers include Rohm Haas, AtoFina, Shell, and Exxon. 

Polybutadiene based polyblends (Table 3.19) are very important plastics with industrial applications, e.g. impact resistance polymers and impact modifiers for rigid poly(vinyl chloride). These polyblends are very susceptible to photo-oxidative degradation, because of the presence of polybutadiene. Intensive studies of the photo-oxidation of the rubber modified polyblends lead to the following conclusions [761-764, 1936] ... 

Perkins, W.G., 1999. Polymer toughness and impact resistance. Polymer Engineering and Science 39, 2445-2460. 

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