电子辐照PVA/CMC共混水凝胶的成胶研究

本试验利用电子辐照PVA/CMC共混水凝胶,通过外观透明度、凝胶分数、溶胀度和红外光谱分析,研究了样品中结构的变化与外观透明度、凝胶分数和溶胀度的关系,以及辐照剂量对样品中结构和性能的影响.结果表明,不同比例的PVA与相同比例的CMC组成的共混水凝胶,经电子辐照后呈现不同的宏观特性.辐照样品萃取后得到的凝胶比萃取前的混合凝胶拥有更强的吸水性,表明辐照PVA/CMC共混凝胶形成了网状结构凝胶.几种竞争反应导致不同辐照剂量下混合凝胶中凝胶含量随PVA含量的变化变得复杂.辐照后样品的红外光谱分析显示,辐照使凝胶中部分仲醇中C上链接的H原子被取代而转变为叔醇,从而产生交联.

Gel properties of PVA/CMC hydrogel under electron beam irradiation

PVA/CMC hydrogels were irradiated using MeV electron beams. By analyzing structures, transparence, gel fraction and swelling ratio of the samples varying with the electron irradiation dose, we studied the gel properties of PVA/CMC hydrogels induced by electron beam irradiation. It was found that hydrogels with different quantities of PVA and the same quantity of CMC behave differently under MeV electron beam irradiation. The irradiated PVA/CMC hydrogels are of strong water absorbability after extraction, which implied that net-structures were formed in the hydrogels after irradiation. Several competing-reactions resulted in a complex relation between the gel fraction and the quantity of PVA. FTIR results showed that electron beam irradiation made secondary alcohol turn to tertiary alcohol by the hydrogen replacement, which led to crosslinking of samples.