Interpenetrating polymer network Brittleness

Interpenetrating Polymer Networks (IPN). Polymerization of vinyl and diene monomers over an already formed molecule held in a pol5uner particle represents a special case of copoljnnerization. The interpenetrating polymer networks (qv) thus formed overcome many of the miscibility and other problems associated with physical blends of individual copolymers and leads to new compositions that are useful for coatings, adhesives, and caulks (14). Polychloroprene IPNs have been made by co-curing copolymers of l-chloro-l,3-butadiene [627-22-5], The 1-chloro-l,3-butadiene comonomer polymerizes in a fashion to increase the allylic chloride concentration in the copolymer backbone. The butadiene copolymer with l-chloro-l,3-butadiene (29) and octyl acrylate copolymer (30) improved the low temperature brittleness, oil resistance, and heat resistance of polychloroprene. 

Biopolymer-based interpenetrating networks (IPNs) - Crosslinking of single polymer networks can lead to brittle materials. Biopolymer-based IPNs can result in materials with good strength, less brittleness and increased flexibility, low shrinking, lower sensitivity to solvents and heat, less wearing, and improved... 

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