牵伸和热处理对聚丙烯熔喷非织造材料结构和力学性能的影响

Effects of Heat Treatment and Drawing on the Structure and Mechanical Properties of Polypropylene Meltblown Nonwoven Materials

熔喷非织造工艺是将熔融的热塑性树脂直接制成超细纤维非织造材料的一步法生产工艺,然而,熔喷非织造材料较差的力学性能限制了其在某些领域的应用.通过自制的热处理设备,在一定牵伸条件下对熔喷试样进行不同温度的热处理,并对其结构和力学性能变化进行了分析.结果表明:经牵伸和热处理后,试样纵向断裂伸长率不断下降,强力不断提高,130℃热处理后的效果最优,纵向强力提高了45.2%;横向强力在热处理后下降,断裂伸长率随温度升高先增大后减小,在80℃时达到最大.因此,经过牵伸和热处理的熔喷非织造材料可适用于对材料纵向强力要求高的应用领域.

Meltblown is an effective process to produce microfiber nonwovens in one step from thermoplastic resins.However,the weak mechanical properties of meltblown nonwoven material restrict its applications.A heat treatment equipment was self-made and PP（polypropylene）meltblown nonwoven materials were heat treated under the same drawing condition.Then the effects of heat treatment and drawing on the structure and mechanical properties of PP meltblown nonwovens were studied.The experimental results indicate that the elongation at break is decreased and the breaking strength in machine direction is enhanced with the increasing of heat treatment temperatures.At the temperature of130℃,the breaking strength of PP meltblown materials in machine direction is increased by 45.2%.While,in cross direction,the elongation at break is increased then decreased,reaching its summit at 80℃;the breaking strength is decreased with the increasing of heat treatment temperatures.Thus,the heat treated meltblown nonwoven materials can be used in the areas where only high strength in machine direction is required.