水溶性Janus型POSS的设计合成及其对PAA/PAM水凝胶力学性能影响的研究

Design and synthesis of water-soluble Janus-type POSS and its effect on mechanical properties of PAA/PAM hydrogel

摘要:

利用丙烯酰氧丙基多面体低聚倍半硅氧烷（Acrylo-POSS）和3-巯基-1-丙烷磺酸盐（MPS）之间的巯基点击反应，一步合成水溶性Janus型多面体低聚倍半硅氧烷（AS-POSS）。通过改变投料比可以调控AS-POSS的水溶性和双键与磺酸钠基团的物质的量比。将AS-POSS与丙烯酸（AA）和丙烯酰胺（AM）共聚制备了一系列不同AS-POSS含量的AS-POSS/PAA/PAM水凝胶，其中AS-POSS质量占单体总质量1%的1% AS-POSS/PAA/PAM水凝胶的平衡溶胀比达到512，断裂伸长率达到1074%，压缩强度为583 kPa，压缩应变为89%，屈服应变为330%，均大于对照组MBA/PAA/PAM水凝胶，表明AS-POSS的引入显著提高了水凝胶的溶胀度，明显增强了水凝胶的韧性、抗压缩性能和动态力学性能。AS-POSS/PAA/PAM水凝胶具有良好的导电性，离子电导率最高可达0.401 S/m。

Abstract:

A novel water-soluble Janus-type polyhedral oligomeric silsesquioxane (AS-POSS) was synthesized by thiol click reaction between acrylo polyhedral oligomeric silsesquioxane (Acrylo-POSS) and 3-mercapto-1-propane sulfonate (MPS) in one step. The water solubility of AS-POSS and the molar ratio of double bond to sodium sulfonate group can be regulated by changing the feed ratio. A series of AS-POSS/PAA/PAM hydrogels with different content of AS-POSS were prepared by copolymerization of AS-POSS with acrylic acid (AA) and acrylamide (AM). When the amount of AS-POSS is 1% of the total monomer mass, the equilibrium swelling ratio of 1% AS-POSS/PAA/PAM hydrogel reaches 512, the elongation at break was 1074%, the compressive strength was 583 kPa and the compressive strain was 89%. The yield strains were 330%, which were higher than those of MBA/PAA/PAM hydrogels in the control group, indicating that the introduction of AS-POSS significantly improved the swelling degree of hydrogels, and significantly enhanced the toughness, compression resistance and dynamic mechanical properties of hydrogels. AS-POSS/PAA/PAM hydrogel has good electrical conductivity. The ionic conductivity of 25%AS-POSS/PAA/PAM hydrogel was the highest with ionic conductivity of 0.401 S/m.