【摘要】 在比较乙烯-辛烯共聚热塑性弹性体(POE)、氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物(SEBS)和凝胶丁腈弹性体(GNBE)增韧聚甲醛(POM)的力学性能基础上,研究了GNBE增韧POM共混物的应力-应变、断裂形貌和热稳定性。结果表明,以GNBE改性POM共混物的力学性能最好。当以质量分数为6%的酚醛树脂为增容剂时,用质量分数为20%的GNBE增韧POM,共混物缺口冲击强度为21 6kJ/m2,扯断伸长率为133 0%,拉伸强度为33 8MPa。当GNBE质量分数为10%时,POM/GNBE共混物应变为未改性POM的2倍。试样缺口冲击断裂形貌分析表明,POM的断裂表面光滑平整,是典型的脆性断裂;而POM/GNBE共混物的断裂表面粗糙。加入质量分数为20%的GNBE,POM/GNBE共混物在空气气氛中的热失重温度有明显的提高。更多还原

【Abstract】 The mechanical and thermal properties of polyoxymethylene (POM) blended with various thermoplastic elastomers were studied. Compared with ethylene-octene copolymer and hydrogenated styrene-butadiene-styrene block copolymer, gel acrylitrile-butadiene elastomer(GNBE) exhibited the better effect on the toughening modification of POM. When mass fraction of 20% GNBE was added to, the notched impact strength,elongation at break and tensile strength of POM/GNBE blends increased to 21.6 kJ/m 2,133.0%,33.8 MPa, respectively. Scanning electron microscope examination showed that the fractured surface of POM was smooth, while it became roughness with the addition of GNBE.更多还原