摘要
利用原位聚合伴随溶胶-凝胶进行的过程,合成了丙烯酸酯改性聚氨酯(PUA)/纳米Si O2(PUAS)复合乳液。通过纳米粒度仪、扫描电子显微镜、透射电子显微镜和热重分析仪等技术手段表征了复合乳液及胶膜的结构和性能。结果表明,纳米Si O2能够均匀地分散在复合材料中,随着原料中前驱体正硅酸乙酯(TEOS)质量分数的增加,复合乳液粒径有所增大,胶膜力学性能和热稳定性明显提高。当TEOS质量分数为8%,胶膜拉伸强度达到16. 8 MPa,邵氏硬度A达到94,最大分解速率温度提高到416℃,且胶膜耐水性明显改善,吸水率降低到2. 1%。
Polyurethane-acrylate/nano-SiO_2(PUAS) composite emulsions were synthesized by in situ polymerization accompanying sol-gel process,in which the hydrolysis reaction and polymerization of monomers were accomplished at the same time. The properties and structure of the films and emulsion were characterized by a laser particle size analyzer,scanning electron microscopy(SEM) and transmission electron microscopy(TEM),etc. The results indicated that with the increase of the mass fraction of tetraethylorthosilicate(TEOS),the thermostability and the mechanical properties of the films were improved remarkably. When the mass fraction of TEOS was 8% in the PUAS composite emulsion,the water absorption of the obtained film was2. 1%,the tensile strength was 16. 8 MPa,the Shore hardness was 94,and the temperature for the maximal thermal mass-loss rate was 416 ℃.
引文
[1]Lin W C,Yang C H,Wang T L,et al. Hybrid Thin Films Derived from UV-curable Acrylate-Modified Waterborne Polyurethane and Monodispersed Colloidal Silica[J]. Express Polym Lett,2012,6(1):2-13.
[2]Maurya S D,Kurmvanshi S K,Mohanty S,et al. A Review on Acrylate-Terminated Urethane Oligomers and Polymers:Synthesis and Applications[J]. Polym-Plast Technol Eng,2018,57(7):625-656.
[3]Zhang S F,Wang R M,He Y F,et al. Waterborne Polyurethane-Acrylic Copolymers Crosslinked Core Shell Nanoparticles for Humidity-Sensitive Coatings[J]. Prog Org Coat,2013,76:729-735.
[4]Yang Z H,Ni A Q,Wang J H. Synthesis and Characterization of Novel Ultraviolet-Curing Polyurethane Acrylate/Epoxy Acrylate/Si O2Hybrid Materials via Sol-Gel Reaction[J]. J Appl Polym Sci,2013,10(1002):2905-2909.
[5]Um M S,Ham D S,Cho S K,et al. Surface Mechanical Properties of Poly(urethane acrylate)/Silica Hybrid Interpenetrating Polymer Network(IPN)Coatings[J]. Prog Org Coat,2016,97:166-174.
[6]Duan Y N,Jana S C,Lama B,et al. Reinforcement of Silica Aerogels Using Silane-End-Capped Polyurethanes[J].Langmuir,2013,29:6156-6165.
[7]Han W S. Synthesis and Properties of Networking Waterborne Polyurethane/Silica Nanocomposites by Addition of Poly(ester amine)Dendrimer[J]. Polym Comp,2013,10(1002):156-163.
[8]Zhang L H,Zhang H,Guo J S. Synthesis and Properties of UV-Curable Polyester-Based Waterborne Polyurethane/Functionalized Silica Composites and Morphology of Their Nanostructured Film[J]. Ind Eng Res,2012,51:8434-8441.
[9]Zhang S W,Yu A X,Liu S L,et al. Effect of Silica Nanoparticles on Structure and Properties of Waterborne UV-curable Polyurethane Nanocomposites[J]. Polym Bull,2012,68:1469-1482.
[10]Qiu F X,Xu H P,Wang Y Y,et al. Preparation,Characterization and Properties of UV-Curable Waterborne Polyurethane Acrylate/Si O2Coating[J]. J Coat Technol Res,2012,9(5):503-514.
[11]Wang Y Y,Qiu X F,Lv Y F,et al. Preparation and Properties of Waterborne Poly(urethane acrylate)/Silica Dispersions and Hybrid Composites[J]. Plast Rubber Compos,2012,41(10):418-425.
[12]LI Hao,CHEN Guangmei,CHEN Wei,et al. Synthesis and Characterization of Core-Shell Acrylicc/Polyurethane Emulsion with Unsaturated Macromolecule Monomer Method[J]. Chinese J Appl Chem,2011,28(10):1135-1142(in Chinese).李昊,陈广美,陈炜,等.大分子不饱和单体法合成具有核壳结构的丙烯酸酯/聚氨酯乳液及表征[J].应用化学,2011,28(10):1135-1142.
[13]ZHANG Mingyue,CHEN Guangmei,ZHANG Xiaoliang,et al. Synthesis and Characterization of Core-Shell Structured Polyurethane Modified by Fluorinated Acrylate[J]. Fine Chem Eng,2011,28(11):1041-1045(in Chinese).张明月,陈广美,张晓亮,等.含氟丙烯酸酯改性聚氨酯核壳乳液的制备及表征[J].精细化工,2011,28(11):1041-1045.
[14]Yang J,Han C R,Duan J F,et al. Interaction of Silica Nanoparticle/Polymer Nanocomposite Cluster Network Structure:Revisiting the Reinforcement Mechanism[J]. J Phys Chem C,2013,117:8223-8230.