臭氧氧化处理法对聚丙烯表面涂装性的改良 Ⅱ.臭氧浓度及臭氧发生气组成对聚丙烯表面氧化过程的影响

讨论了用臭氧氧化法对聚丙烯表面进行涂装性改良时,臭氧浓度和臭氧发生气组成对聚丙烯表面氧化过程的影响。我们发现,随臭氧浓度的增加,各种聚丙烯表面上COOH基的生成速率变大,而OH基的生成速率变小,且表面上COOH基和OH基的生成比变大。在相同的臭氧浓度下,COOH基的生成速率和聚丙烯种类无关,各种聚丙烯表面上COOH的生成速率大体相等。而OH基的生成速率及COOH基、OH基生成比和聚丙烯的种类有关,就COOH基和OH基生成比而言,其大小顺序为均聚物>嵌段共聚物>无规共聚物。臭氧发生气组成对聚丙烯表面氧化过程有很大的影响。和臭氧发生气为空气时的情况相比,当臭氧发生气为氧气时,即使其体系中臭氧浓度的变化很小,也会引起较大的表面氧吸收量或表面氧化分解量的变化。

Improvraent of the Coating Properties of Polypropylene Surface by Ozonization II Effect of Ozone Concentration and Ozone-producing Gas Composition on the Oxidation Process of the Polypropylene Surfaces

The effects of ozone concentration and ozone - producing gas compositions on the oxidation process of the PP surfaces have been studied in this paper. It was found that with the increase of ozone concentration , the producing rate of COOH groups increased while that of OH decreased , and the ratio of the relative amount of COOH groups on the surface also increased. At the same ozone concentration level , the producing rates of COOH groups had no relation to the kinds of PP , while the producing rate of OH groups and the ratio of the relative amount of COOH groups to OH groups varied with the kinds of PP. So far as the ratio of the relative amount of COOH groups to OH groups was concerned . the sequence could be expressed as homopolymer>block copolymer>random copolymer. The composition of ozone-- producing gas had great influence on the oxidation process of PP surfaces. Compared with the air , when the oxygen was used as ozone producing gas , even a small change of ozone concentration could cause a great change in the oxygen -absorption amount or the oxidation-- decomposition amount of PP surfaces.