Determination of molecular weight in polyvinylmethylsiloxane by positron annihilation

In this paper a linear relation between the life time of positron annihilation and molecular weight of weight average in polyvinylmethylsiloxane is simple deduced according to S.Y. Chuang's hypothesis. The experiment results with polyvinylmethylsiloxane show that there is a linear relation between the life time of positron annihilation and molecular weight of weight average. The molecular weight of the polyvinylmethylsiloxane is determined by this linear relation. The result is compared with other results obtained by the viscosimetry method. The difference between them is less than 3.7%. The experimental results is discussed and the authors put forward the method to determine molecular weight