几种无纺布聚丙烯专用料的性能研究

选取了国内无纺布企业主要用的几种聚丙烯专用料，测定了其力学性能、流动性能，并在此基础上考察了不同热处理温度下的熔融特性以及不同降温速率下的结晶特性。结果表明：PP S2040的熔体质量流动速率较高，易于加工成型，但对温度的依赖性较大。PP1700的拉伸强度、拉伸屈服强度和缺口冲击强度比PP S2040、Exxon3155高，而断裂伸长率却最低。这是由于PP1700的熔体流动速率小，相对摩尔质量大，强度相对提高。热处理后，由于聚丙烯的结晶程度更加完善，几种专用料的熔融起始温度Tm0、熔融峰温Tmp均有所上升。随着降温速率增加，低温进入晶区的部分增多，使结晶范围变宽，结晶温度Tc和结晶峰都向低温方向移动，结晶度有所增加。在相同的降温速率下，PP S2040的结晶时间ts略小，而结晶焓较高，说明在较短的时间内达到较高的结晶度，结晶速度较快。

Study on Behavior of Some Kinds of Special PP Compound for Non-woven Fabric

The mechanical properties and flowability of some kinds of special PP compound widely used in the non-woven fabric enterprises at home were tested, the melting characteristics on different heating temperature and the crystal characteristics at different cooling rate were studied. It was found that PP S2040 had the highest melt flow rate and could be easily processed, while it largely depended on temperature. Owing to the lowest MFR and largest molecular weight of PP 1700, the tensile strength, yield strength and notched impact strength of PP 1700 were better than those of PP S2040 and Exxon 3155, but the elongation at break of PP 1700 was the lowest. After heating, PP had well crystallization degree and the initial melting temperature and peak melting temperature all rose up. With the increase of the cooling rate, the crystallization area extended and crystallization peek decreased. When the cooling rate was the same, the ts of PP S2040 was low, but the crystalline enthalpy of PP S2040 was high, which showed a higher crystallinity could be achieved within a short time and the crystallization rate was high.