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从无規交联理論出发,討論和分析了交联过程中溶胶部分特性粘数的变化基木規律,考虑到支化效应对特性粘数的依賴性后,得到溶胶部分特性粘数同溶胶分数和分布寬度参数間的一般关系式(16),当溶胶部分的交联指标很小时(γn<0.5),其支化效应可近似不計。建議一种从溶胶分数和溶胶部分特性粘数的实驗数据按(13)和(17)式估計高聚物起始分子量分布的簡易新方法,应用此种方法估計了高压聚乙烯和天然橡胶的起始分子量分布,得到σ=0.3,(?)_(wo)/(?)_(no)=4.3(对高压聚乙烯)和σ=0.6,(?)_(wo)/(?)_(no)=2.7(对天然橡胶)。它們分别同溶胶分数和凝胶的体积溶胀比和从溶胶分数和溶胶部分的数均分子量所确定的σ值很好地一致。并且溶胶部分特性粘数計算值同实測值亦較好地一致。最后对无規交联理論又一次进行了驗証。
Based on the theory of random cross-linking, the change of intrinsic viscosity of sol during cross-linking is discussed and analyzed. Taking into account the dependency of branching effect on intrinsic viscosity, the intrinsic viscosity of sol and the sol fraction And the distribution width parameter (16), the branching effect of the sol portion can be approximated when the cross-linking index of the sol portion is small (γn <0.5). A new and simple method to estimate the initial molecular weight distribution of polymers according to (13) and (17) is proposed based on the experimental data of the sol fraction and the intrinsic viscosity of the sol. Using this method, the high pressure polyethylene and natural rubber The initial molecular weight distribution gave σ = 0.3, (?) - (wo) / (?) - (no) = 4.3 for high pressure polyethylene and σ = 0.6, (no) = 2.7 (for natural rubber). They agree well with the sol fraction and the volume swell ratio of the gel and the σ values determined from the sol fraction and the number average molecular weight of the sol fraction, respectively. And the intrinsic viscosity of the sol part calculated value is also consistent with the measured value. Finally, the theory of random cross-linking was verified.