聚乙烯醇/天然橡胶共混物的制备及其性能研究

利用环氧化天然胶乳作为界面改性剂,采用胶乳共混法将聚乙烯醇（PVA）溶液同天然胶乳进行混溶,制备了PVA/天然橡胶（NR）的共混物,通过电子万能材料试验机、动态热机械分析仪、热老化箱和臭氧老化箱,研究了共混物力学性能、玻璃化转变温度、老化性能以及耐溶剂抽出性。结果表明,PVA的加入明显提高了NR的撕裂强度和硬度,而共混物的拉伸强度和断裂伸长率随着PVA含量的增加都出现下降的趋势;随着PVA含量的增加,NR的玻璃化转变温度呈现先增加后降低的趋势;随着PVA含量增加,共混物各试样对乙醇的耐抽出能力相差不大,对水的耐抽出能力逐步变弱。热空气老化对材料的力学性能影响明显,而臭氧老化由于时间较短,对材料的力学性能影响不明显。老化实验对材料的性能变化率影响显著。

Preperation and property of polyvinyl alcohol/natural rubber blends

Polyvinyl alcohol/natural rubber blends（PVA/NR） were prepared using epoxidized natural rubber latex as a interfacial modifier.DMA,aging oven and mechanical test were used to study the glass-transition temperatue,aging property,mechanical property and solvent resistance of PVA/NR blends.Mechanical test showed that the PVA significantly improved tear strength and hardness of the NR.The tensile strength and elongation at break decreased significantly along with the PVA increasing.DMA analysis showed the glass-transition temperature was increased firstly,then decreased along with the PVA increasing.The solvent resistance ability of the blends was not significant for ethanol,but weaker for water along with the PVA increasing.Hot air aging had obviously impact on the mechanical properties of the material,however,the ozone aging had no significant effect on the mechanical properties of the material due to the short time.The performance retention of the material properties was taken effect significantly because of the aging test.