端羟丙基含氟聚硅氧烷的合成及其改性水性聚氨酯性能

Synthesis of hydroxyl terminated fluorinated polysiloxane and properties of its modified waterborne polyurethane

采用端氢含氟聚硅氧烷和烯丙基醇为原料,以氯铂酸为催化剂,经硅氢加成合成端羟丙基含氟聚硅氧烷,并应用于改性水性聚氨酯。研究了合成因素对双键转化率的影响,优化了合成工艺条件;采用傅里叶红外、核磁以及凝胶渗透色谱对合成产物结构加以表征,并测定了改性水性聚氨酯乳液、胶膜和涂层织物的性能。结果表明,副反应抑制剂能有效抑制硅氢加成反应的副反应。端羟丙基含氟聚硅氧烷合成优化工艺条件为:副反应抑制剂用量0.2%,催化剂质量浓度60 mg/L,反应温度75℃,反应时间4 h。改性水性聚氨酯乳液粒径为45 nm,胶膜水接触角及吸水率分别为106.8°和28.1%。相对未改性水性聚氨酯,改性水性聚氨酯涂层织物拒水性得到明显改善。

Hydroxypropyl terminated fluorinated polysiloxane was synthesized via hydrosilylation,with hydrogen terminated fluorinated polysiloxane and allyl alcohol as raw materials and chloroplatinic acid as catalyst,and applied in preparing modified waterborne polyurethane.Influence of synthetic process factors on the double bond conversion was researched,the synthesis process conditions were optimized,the structure of the synthesis product was characterized by FT-IR、1H-NMR and gel permeation chromatography （GPC）,and the properties of emulsion and film of modified waterborne polyurethane and coated fabric were measured.The results showed that the side reaction inhibitor could effectively inhibit the side reaction of hydrosilylation.The optimal synthesis process conditions of hydroxypropyl terminated fluorinated polysiloxane were that：the dosage of side reaction inhibitor was 0.2 %,the dosage of the catalyst was 60 mg/L,the reaction temperature was 75 ℃,and reaction time was 4 h.The particle size of the emulsion of waterborne polyurethane was 45 nm,and the water contact angle and the water absorption of the film were 106.8°and 28.1% respectively.Compared with the unmodified polyurethane,the water resistance of the fabric coated with the modified waterborne polyurethane was improved significantly.