以生物基二聚脂肪酸制备聚氨酯丙烯酸酯树脂及其性能研究

为了减缓石油资源消耗,利用可再生二聚酸制备聚氨酯丙烯酸酯。将二聚脂肪酸(DA)与乙二醇(EG)以不同的物质的量比缩合制得3种不同羟值的聚酯二元醇(A-1、A-2、A-3),再依次通过与甲苯二异氰酸酯(TDI)、丙烯酸羟乙酯(HEA)反应引入丙烯酸酯基团,从而制得3种可光固化的聚氨酯丙烯酸酯树脂(B-1、B-2、B-3)。利用傅立叶变换红外光谱(FT-IR)对原料及合成产物进行了结构表征;采用实时红外分析(RT-IR)研究了不同条件下树脂的光固化性能;采用万能试验机、差示扫描量热仪(DSC)、热重分析仪(TGA)分析测试了固化膜的力学性能、玻璃化转变温度和热稳定性;同时测试了固化膜的接触角及铅笔硬度等。结果表明:随着二聚酸含量的升高,所制得的聚酯二元醇黏度和数均相对分子质量增大,羟值降低。最终所制备的聚氨酯丙烯酸酯树脂固化膜的热稳定性和附着力基本相同,但随着羟值含量的降低,软段部分增加,双键含量降低,交联密度下降,导致固化膜铅笔硬度、吸水率降低,柔韧性增加。

Preparation and Properties of Polyurethane Acrylate Resin from Bio-Based Dimer Fatty Acids

In order to cut down the consumption of petroleum resources，the renewable dimer acid was used to prepare polyurethane acrylate to meet the concept of sustainable development.Three kinds of polyester diols（A-1，A-2，A-3）with different hydroxyl values were prepared through condensation of dimer fatty acid and ethylene glycol（EG）at different molar ratio，which were further reacted with toluene diisocyanate（TDI） and hydroxyethyl acrylate（HEA） to introduce acrylate groups，resulting in three photocurable polyurethane acrylate resins（B-1，B-2，B-3）. The structures of the raw materials and synthesized products were characterized by Fourier transform infrared spectroscopy（FT-IR）； Real-time infrared（RT-IR）analysis was used to study the photo-curing properties under different conditions；A universal testing machine，a differential scanning calorimeter（DSC）， and thermal gravimetric analyzer（TGA）were used to analyze and test the mechanical properties，glass transition temperatures，and thermal stability of the cured resin film，and the contact angle and pencil hardness of the coating were also tested. The results showed that as the dimer acid content increased，the viscosity and number average molecular weight of the prepared polyester diol increased，and the hydroxyl value decreased The thermalstability and adhesion properties of the final cured polyurethane acrylate resin film were almostthe same，but as the hydroxyl value content decreased，the soft segment part increased，the double bond content decreased，and the crosslink density decreased，resulting in a decrease of pencil hardness and water absorption of the cured film，and increase of the flexibility.