【摘要】 为了改善二聚酸酰胺尼龙(DAPA)的综合性能,用熔融缩聚方法制备了系列短链己二酸改性的DAPA共聚物,采用IR,UV-Vis,DSC和TG等研究了己二酸对DAPA凝聚态结构、热性能及物理力学性能的影响.实验结果表明:己二酸的加入可提高DAPA的密度、熔点、吸水率、拉伸和抗弯性能,缺口冲击强度、热稳定性降低;当己二酸加入量大时,产生脆韧转变,抗冲击性能反而下降.己二酸的存在可促进共聚物从γ到α,β晶型的晶相转变,并提高其结晶程度,还可降低C—N键的离解能,调变共聚物分子间缔合氢键的数量、σ-π*电子离域方向和离域程度,有助于酰胺基团的活化.更多还原

【Abstract】 The integrated properties of dimer acid-based polyamide nylon(DAPA) were improved with adipic acid embedded into the main chain of a series of DAPA copolymers by melt phase polycondensation method.The effect of adipic acid on the state of aggregation,thermal,physical and mechanical properties of DAPA(dimer acid-based polyamide)was investigated by IR(infrared spectra),UV-Vis(UVVis spectra),DSC(differential scanning calorimeter) and TG(thermogravimetric analysis).The results show that addition of a small amount of adipic acid to DAPA increases the density,melting point,water absorption,and decreases the Izod notched impact strength,and deteriorates the thermal stability.However,a large amount of adipic acid causes a rapid decrease in the impact strength due to brittle-ductile transition.The presence of adipic acid leads to the change of phase structure from γ to α,β crystal forms,and increases the content of α,β crystal phases.It can also reduces the energy of dissociation of the C—N bond,and modulates quantities of hydrogen bonds of intra and inter molecules,and delocalized direction and delocalized degree of σ-π* electrons,which favors the activation of the amide bond.更多还原