摘要
<正> 氯醇橡胶具有优良的耐油、耐热、耐寒和耐老化等性能。其溶液性质已有报道,并订定了一些Mark-Houwink方程。过去所用试样分子量一般偏低,也未见用小角激光光散射法测定其分子量的报道。本文介绍高分子量((?)=7.0×10~5～1.3×10~6)无定形氯醇橡胶的溶液性质。
This paper presented the fractionation of the amorphous polyepichlorohydrin sample with a high molecular weight by reprecipitation with toluene as the solvent and ethyalcohol as the precipitant (50℃ ). The intrinsic viscosities [η] of the narrow distribution fractions in the solvents cyclohexanone (35℃) and tetrahydrofuran (25℃) were determined, the average values of the constants of Huggins equation and kraemer equation were obtained by calculation as k' = 0. 360,β=0. 146(in THF) ; k' = 0. 356,β=0. 148 (in cyclohexanone). The weight-average molecular weight of the fractions were measured experimentally by the low angle laser light scattering (LALLS) photometer, and the Mark-Houwink equations were calibrated as [η]= 2. 37 × 10-5Mw0.79(dL/g,THF, 25℃ ), [η]= 1. 36 × 10-5Mw0.85 (dL/ g, cyclohexanone, 35℃). The unperturbed parameters of molecular chains of polyepichlorohydrin were obtained according to the stockmayer-Fixman equation, k0= 5. 25 ×10-4 (dL/g),σ=l. 57,C∞ = 4. 91(THF,25℃);k0= 4.97× 10-4(dL/g), σ=l. 54,C∞ = 4. 73(cyclohexanone, 35 ℃).
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第10期1065-1067,共3页
Chemical Journal of Chinese Universities
关键词
氯醇橡胶
溶液性质
Polyepichlorohydrin, Mark-Houwink equation, Unperturbed molecular parameter, Low angle laser light scattering
