多巴胺改性海藻酸钠/聚丙烯酰胺水凝胶的制备及其性能

Preparation and properties of dopamine-modified sodium alginate/polyacrylamide hydrogel

以1-(3-二甲氨基丙基)-3-乙基碳二亚胺/N-羟基琥珀酰亚胺(EDC/NHS)为催化剂,通过多巴胺(DA)与海藻酸钠(SA)反应,制得含有邻苯二酚基团的多巴胺改性海藻酸钠(SA-DA);采用自由基聚合法,以SA-DA和丙烯酰胺(AM)为主要原料,N,N’-亚甲基双丙烯酰胺(Bis)为交联剂,过硫酸铵(APS)为引发剂,制备了SA-DA/PAM双网络(DN)水凝胶.采用1H NMR、UV-Vis对SA-DA组成进行表征;采用拉力试验机及SEM对SA-DA/PAM水凝胶的力学性能及形貌进行表征.考察四甲基乙二胺(TEMED)的加入、SA-DA浓度及Bis含量对水凝胶强度和粘附性的影响.结果表明,加入TEMED后水凝胶的强度和粘附性能均有下降.当SA-DA浓度为15 mg/mL,Bis含量为AM的0.15 mol%时,SA-DA/PAM水凝胶有较高的强度和较好的粘附性,粘附性为9.8 kPa,拉伸强度为391.8 kPa,断裂伸长率为486.0%.与SA/PAM水凝胶相比,拉伸强度增加了6.3倍,断裂伸长率提升了4.1倍,粘附性提高了2.4倍.

Dopamine-modified sodium alginate(SA-DA)containing catechol groups was prepared by the reaction of dopamine with sodium alginate(SA)with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide/N-hydroxysuccinimide(EDC/NHS)as the catalyst.Then,SA-DA/PAM double network(DN)hydrogel was prepared by free radical polymerization,using SA-DA and acrylamide(AM)as the main raw material,N,N’-methylene bisacrylamide(Bis)as the crosslinking agent,and ammonium persulfate(APS)as initiator.The composition of SA-DA was characterized by~1H NMR and UV-Vis.The mechanical properties and morphology of SA-DA/PAM hydrogel were characterized by a tensile testing machine and SEM.The effects of four methyl ethylenediamine(TEMED),SA-DA concentration,and Bis content on the strength and adhesion of hydrogels were investigated.The results showed that the strength and adhesion of hydrogel decreased after adding TEMED.When the SA-DA concentration was 15 mg/mL and the Bis content was 0.15 mol%of AM,the SA-DA/PAM hydrogel had higher strength and better adhesion.The adhesion was 9.8 kPa,the tensile strength was 391.8 kPa,and the elongation at break was 486.0%.Compared with the SA/PAM hydrogel,the tensile strength increased by 6.3 times,the elongation at break increased by 4.1 times,and the adhesion increased by 2.4 times.