Plasticizers unreacted monomer acting

Another way to view this phenomenon is to consider the curing cyanoacrylate as a plasticizer-polymer mixture in which the unreacted monomer is the plasticizer. The Tg of a plasticized polymer is lower than that of unplasticized polymer, and the Tg drop is governed by the amount and efficiency of the plasticizer. In the present case, even if the polymer portion of the mixture has reached its ultimate Tg, the remaining monomer acts as a plasticizer that lowers the Tg to a value about 30 C above Tcure-... 

An interesting method for producing plastic microspheres is disclosed by Bayer AG (13). The microspheres consist of vinyl chloride-ethylene copolymers. This method involves the use of the difference of monomer reactivity between vinyl chloride and ethylene. Upon radical polymerization of the two monomers at 50°C, vinyl chloride reacts faster than does ethylene, and unreacted monomeric ethylene then remains in the resulting copolymer jn-oduced by the pearl polymerization. The monomer can then act as the blowing agent. 

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