抄録
In order to determine the heat of polymerization of bone cement made mostly from methyl methacrylate polymer, methyl methacrylate - styrene copolymer and methyl methacrylate monomer, the authors polymerized the cement in the building insulation at ambient temperature under atmospheric pressure, and measured both the temperature of the cement θ during the polymerization and the specific heat capacity of the polymerized cement c_<bc>. The experiments were carried out at ambient temperatures θ_<amb> of 17 to 28℃. During the polymerization, the temperature of cement increases transiently to the top temperature θ_<max> and never decreases. The difference ΔT between the cement and ambient temperatures slightly increases with increasing the mass of cement, and it exceeds 88 K. The polymerization reaction takes around 700 sec. The specific heat capacity increases from 1.4 to 2.1 kJ/(kg・K) with increasing the temperature from 28 to 122℃. The heat of polymerization q_0 estimated based on the results of the temperature and the specific heat capacity reaches around 145 J/g. Then the heat loss from the cement samples is estimated to be within 17.9 J/g.
