研究了在天然鲜胶乳中分别以盐酸羟胺、硫酸羟胺、盐酸联胺、硫酸联胺、水合联胺、盐酸氨基脲、苯胺等作恒粘剂,采用微生物凝固工艺制备的天然橡胶(NR)在常温贮存过程中门尼粘度的变化。结果表明,盐酸羟胺、硫酸羟胺的用量在0.05%(对干胶)时就可以使NR的门尼粘度稳定,可制得低粘度的恒粘NR;水合联胺的用量需要达到0.20%~0.30%时,可制得中高粘度的恒粘NR;盐酸氨基脲的用量在0.05%时,可制得中等粘度的恒粘NR,用量在0.10%~0.20%时,可制得低粘度的恒粘NR;苯胺的用量在0.01%~0.03%时,可制得中等粘度的恒粘NR,用量在0.05%~0.20%时,可制得高粘度的恒粘NR;硫酸联胺和盐酸联胺无法使NR的门尼粘度稳定,但它们能使NR的门尼粘度增加。
The effect of several viscosity stabilizers(hydroxylamine hydrochloride,hydroxylammonium sulphate,hydrazine dihydrochloride,hydrazine sulfate,hydrazine hydrate,semicarbazide hydrochloride,aniline) on the Mooney viscosity of NR prepared by biological coagulation technology during storage at room temperature were studied by adding viscosity stabilizers into fresh latex.The results showed that the constant viscosity natural rubber with low-viscosity obtained when the dosage of hydroxylamine hydrochloride,or hydroxylammonium sulphate was 0.05%(relative to the weight of NR).And the constant viscosity natural rubber with medium or high viscosity was obtained when the dosage of hydrazine hydrate was 0.20%~0.30%.The constant viscosity natural rubber will has medium viscosity in case of the dosage of semicarbazide hydrochloride is 0.05% and the constant viscosity natural rubber had low-viscosity with the dosage being 0.10%~0.20%.The constant viscosity natural rubber had medium viscosity if the dosage of aniline was 0.01%~0.03%,and the constant viscosity natural rubber had high viscosity if the dosage of aniline was 0.05%~0.20%.The viscosity of natural rubber was high and unstable when adding hydrazine sulfate or hydrazine dihydrochloride into fresh latex.