Straus Sidney, Wall Leo A
J Res Natl Bur Stand A Phys Chem. 1961 May-Jun;65A(3):221-226. doi: 10.6028/jres.065A.026. Epub 1961 Jun 1.
The rates of volatilization of linear polymers of ethylene and propylene and their copolymers are somewhat characteristic of random degradation in that a maximum occurs in the rate curve for all polymers studied. Increasing amounts of propylene in the copolymer showed increases in the maximum rate on thermal decomposition. Minute inorganic and organic impurities added to the polypropylene have considerable effect on the thermal stability of the polymer by lowering the rates of volatilization and increasing the activation energy. Possibly there is an inhibition of the free-radical chain process, and the overall reaction becomes more like that for the initiation process. Rate studies and volatile decomposition products for a fully deuterated linear polyethylene were also determined, and its activation energy was calculated to be 70 kcal/mole, which is very close to the value (72 kcal/mole) calculated for the nondeuterated polymer. The effect of a large dose of beta-radiation on a linear polyethylene was also determined. Results suggest that scissions in the chain, as well as cross links, are caused by the radiation.
乙烯和丙烯的线性聚合物及其共聚物的挥发速率在某种程度上是无规降解的特征，因为在所研究的所有聚合物的速率曲线中都会出现一个最大值。共聚物中丙烯含量的增加表明热分解时最大速率增加。添加到聚丙烯中的微量无机和有机杂质通过降低挥发速率和增加活化能，对聚合物的热稳定性有相当大的影响。可能存在对自由基链过程的抑制，并且整体反应变得更类似于引发过程。还测定了全氘化线性聚乙烯的速率研究和挥发性分解产物，其活化能计算为70千卡/摩尔，这与非氘化聚合物计算的值（72千卡/摩尔）非常接近。还测定了大剂量β辐射对线性聚乙烯的影响。结果表明，辐射会导致链的断裂以及交联。
