Hardness of ``Late" and Weakly Crosslinked Polymethylmetacrylate and its Relationship to Chain Statistics

Authors: Güngör GÜNDÜZ, Metin KİRKİN

Abstract: The hardness of ``late" and weakly crosslinked polymethylmethacrylate was determined experimentally. The change in hardness can be expressed by, H=h_0+h kx (kx-1)(1-C)^{kx-2}C^2 where C is the fraction of cross-linker, x the number of monomer units, and kx denotes the linkages or units formed on the linear chain after the addition of cross-linker. h and h_0 are constants and H is hardness of the polymer. The relation given above describes an asymmetric curve. Scaling relations exits between k,Cpolymethylmetacrylate, these relations are k\sim C^{ -0.8}, M\sim C^{-0.2}, and k\sim M^4.