The fluoro alcohol-terminated branched polyurethanes with different fluorine content (FABPU-0, FABPU-1 and FABPU-2) was successfully synthesized via step-by-step polymerization in which polytetramethylene oxide glycol (PTMG-2000) and 4,4′-diphenylmethane diisocyanate (MDI) were used as raw materials, 1,4- butanediol (BDO) as the chain extender, pentaerythritol as crosslinking agent, anhydrous ethanol (EtOH) or perfluorinated hexyl alcohol (S104) as end capping agent. The molecular structure and relative molecular weight of aromatic polyurethane (PU) and FABPU were characterized by means of Fourier-transform infrared (FTIR) and Gel permeation chromatography (GPC). The results showed that the average molecular weight of FABPUs increased compared with that of PU. The characterization results by thermogravimetric (TG) and X-ray diffraction (XRD) showed that the crystallinity of FABPU-2 was enhanced 148.3 %, as well as the thermal decomposition temperature was raised by 38 ℃. The yellowing resistance of FABPU and aromatic fluorine-free PU was investigated by the change of yellowness index (YI), chromatic aberration (ΔE). The results showed that compare with that of aromatic fluorine-free PU, YI of FABPU-2 decreased to 14.3 from 32.48, as well as ΔE reduced to 5.07 from 16.34. Moreover, the water contact angle of FABPU-2 increased to 141° from 89.3°. These indicated that the crosslinking of pentaerythitol and the introduction of fluorine obviously improved the hydrophobicity and yellowing resistance of aromatic PU.

通过以下方法成功合成了不同氟含量的氟代醇封端的支链聚氨酯（FABPU-0，FABPU-1和FABPU-2）。以聚四氢呋喃二醇（PTMG-2000）和4,4'-二苯基甲烷二异氰酸酯（MDI）为原料，1,4-丁二醇（BDO）为扩链剂，季戊四醇为交联剂的分步聚合，无水乙醇（EtOH）或全氟化己醇（S104）作为封端剂。利用傅里叶变换红外光谱（FTIR）和凝胶渗透色谱（GPC）对芳香族聚氨酯（PU）和FABPU的分子结构和相对分子量进行了表征。结果表明，FABPU的平均分子量较PU有所增加。热重（TG）和X射线衍射（XRD）表征结果表明，FABPU-2的结晶度提高了148.3％，热分解温度提高了38℃。通过黄度指数（YI），色差（ΔE）的变化研究了FABPU和芳香族无氟PU的耐黄变性。结果表明，与芳香族无氟聚氨酯相比，FABPU-2的YI从32.48降低到14.3，ΔE从16.34降低到5.07。此外，FABPU-2的水接触角从89.3°增加到141°。这些表明季戊四醇的交联和氟的引入明显改善了芳族PU的疏水性和抗黄变性。FABPU-2的水接触角从89.3°增加到141°。这些表明季戊四醇的交联和氟的引入明显改善了芳族PU的疏水性和抗黄变性。FABPU-2的水接触角从89.3°增加到141°。这些表明季戊四醇的交联和氟的引入明显改善了芳族PU的疏水性和抗黄变性。