负离子型聚氨酯离聚体水分散过程的相反转

Phase reversion of anion polyurethane during water dispersion

用异佛尔酮二异氰酸酯、聚己二酸新戊二醇酯和二羟甲基丙酸(DMPA)合成了负离子型聚氨酯离聚体,研究了该类离聚体在水分散过程中的相反转变化,讨论了DMPA质量分数和水分散温度对相反转过程的影响。结果表明,DMPA质量分数增加或水分散温度提高,可使相反转所需的时间缩短,分散液粒子粒径变小,粒径分布更均匀,黏度增大。水分散温度的作用较DMPA更为明显。差示扫描量热分析表明,水分散过程破坏了亲水性硬链段的有序性。傅里叶变换红外光谱分析表明,聚氨酯水分散液用乙二胺扩链后,脲羰基的氢键化程度随DMPA质量分数的增加、水分散温度的提高而提高。

A series of polyurethane anionomers were synthesized from isophorone diisocyanate, polyneopentanediol adipate and dimethanol propionic acid （DMPA）. The phase reversal process during water dispersion of the anionomer were followed, and influence of mass fraction of DMPA as well as the water dispersion temperature on the resulted phase reversed dispersion were investigated. It was discovered that the time necessary for phase reversion became shorter, the average diameter smaller and the distribution of diameter of the dispersed particles more uniform, the viscosity of dispersion higher, if the mass fraction of DMPA or the temperature,at which the water dispersion was carried out, increased. The dispersion temperature could be more effective than the mass fraction of DMPA. Differential scanning calorimetry analysis revealed clearly that order of hydrophilic hard segments was destroyed after water dispersion. Fourier transform infrared spectroscopy analysis demonstrated that the hydrogenbonding of ureacarbonyls was stronger with higher dipersion temperature and more mass fraction of DMPA after the chain extender ethyidiamine was added into the polyurethane anionomers dispersion.