一种核壳型粒径可控的纳米微球的制备及性能研究

Preparation and Performance of Particle Size Controllable Polyacrylamide Nano-microspheres with Core-shell Structure

摘要:

以具有较强吸水膨胀特征的丙烯酰胺（AM）和丙烯酸（AA）作为主要聚合单体，以2-丙烯酰胺-2-甲基丙磺酸(AMPS)和甲基丙烯酰氧乙基三甲基氯化铵（DMC）作为功能性单体，通过反相乳液二次聚合制备出P(AM-AA-AMPS-DMC)核壳型微球乳液。利用FTIR、TG、TEM、激光粒度分析仪、流变分析仪、稳定性分析仪等对聚合物微球乳液进行表征，结果显示，AM、AA、AMPS、DMC四种单体已聚合，且P(AM-AA-AMPS-DMC)热稳定性良好，微球呈表面光滑、分布均匀的核壳型结构，其乳液存放6个月仍稳定。通过测定不同温度下和不同矿化度的盐水中的微球膨胀率表征了其耐温、耐盐性。实验结果表明，随着老化时间的增长，微球粒径从260nm膨胀至1168nm；随着温度的升高，膨胀率呈现增大的趋势，在60℃下，P(AM-AA-AMPS-DMC)的微球吸水膨胀率达4.1倍。随剪切速率的增大，乳液呈剪切变稀的特性，且其具有一定的粘弹性。

Abstract:

Theacrylamide(AM) and acrylic acid(AA)withstrong waterabsorption andexpansibilitywere used as main monomers,with 2-acrylamide-2methyl propane sulfonic acid(AMPS) and methyl acrylyl ethyl trimethyl ammonium chloride(DMC) as functional monomer, and a core-shell typeP(AM-AA-AMPS-DMC)nano-microsphereswas preparedby inverse emulsion secondary polymerization.Thepolyacrylamidenano-microspheres were characterized by using FTIR,TG,XRD,TEM,laser particle size analyzer,rheological analyzer and stability analyzer.The results show that monomers AM, AA, AMPS and DMChavepolymerized completely, and P(AM-AA-AMPS-DMC)microspheres have good thermal stability, with smooth surface,uniform distribution and core-shell type structure.Thestorage stability of the nano-microspheresemulsionismorethan6 months.Theheat resistance and salt resistance of the nano-microspheres were characterized by testing expansion rateof nano-microspheresinmineralized waterwithsalinityand at differenttemperature. The experimental results show thatthe average particle size of nano-microsphereswas expanded from 260nm to1168nm as the prolongating of ageing time. Theexpansion rateincreasedwith temperature increasing andtheexpansion rateof P(AM-AA-AMPS-DMC)nano-microspheresat60℃reached to4.1times.With the increase of shear rate,the P(AM-AA-AMPS-DMC)emulsion shows the shear thinning behavior and it has a particularviscoelasticity.