异形聚氨酯弹性体渐变材料的制备与性能研究

Preparation and Properties of Special-Shaped Polyurethane Elastomer Gradient Material

TDI型或MDI型聚氨酯密封在大型机械设备高线速度、高压工况下,材料摩擦生热量较大易达到材料长期使用温度70℃,为了解决材料耐温性不佳导致使用性能严重衰减问题,采用1,5-萘二异氰酸酯(NDI)、聚四氢呋喃二醇(PTMG-1000)、聚己内酯多元醇(PCL-2000)、1,4-丁二醇(BDO)、三羟甲基丙烷(TMP),在异形密封唇口部位和底座引入聚四氟乙烯制备异形聚氨酯弹性体渐变材料。研究PTMG-1000/PCL2000、TMP/BDO和聚四氟乙烯的含量对异形聚氨酯弹性体渐变材料的耐老化性、冲击回弹、压缩永久变形、热稳定性、耐磨性和聚四氟乙烯加工分散性的影响。结果表明:PTMG-1000与PCL2000质量比为1∶2,TMP与BDO质量比为1∶1.5,聚四氟乙烯含量为10%时,异形密封渐变材料的长期使用温度提高至130℃,唇口湿摩擦系数降低24%,唇口每米湿摩擦生热量降低18%,唇口体积磨耗量降低37%,腰部冲击回弹提高10%、冲压缩永久变形量降低39%,热稳定性和聚四氟乙烯加工分散性最佳。

TDI type or MDI type polyurethane seal under the high linear speed,high pressure working conditions of large mechanical equipment,material friction heat generation is large,and is easy to reach the long-term use temperature of the material 70℃,in order to solve the problem of poor temperature resistance of the material leads to serious attenuation of the performance.Special-shaped polyurethane elastomer gradient materials were prepared by using 1,5-naphthalene diisocyanate(NDI),polytetrahydrofuran glycol(PTMG-1000),polycaprolactone polyol(PCL-2000),1,4-butanediol(BDO),trimethylolpropane(TMP),introducing polytetrafluoroethylene(PTFE)at special-shaped sealing lip and base.The effects of the content of PTMG-1000/PCL2000,TMP/BDO and lip PTFE on the aging resistance,impact rebound,compression permanent deformation,thermal stability,wear resistance and processing dispersion of PTFE on specialshaped polyurethane elastomer gradient materials were studied.The results show that when the mass ratio of PTMG-1000 and PCL2000 is 1∶2,the mass ratio of TMP to BDO is 1∶1.5,and the content of PTFE is 10%,the long-term service temperature of special-shaped sealing gradient material is increased to 130℃,the wet friction coefficient of lip is decreased by 24%,the heat generated by wet friction per meter of lip is decreased by 18%,the volume wear of lip is reduced by 37%,the impact rebound of the waist is increased by 10%,and permanent deformation of punching compression is reduced by 39%,the thermal stability and the processing dispersion of PTFE are the best.