Thermoreversible Block Copolymer Worm Gels Using Binary Mixtures of PEG Stabilizer Blocks
Thermoreversible Block Copolymer Worm Gels Using Binary Mixtures of PEG Stabilizer Blocks
复制标题
DOI：
10.1021/acs.macromol.8b02491
复制
发表时间：
2019-02
期刊：
影响因子：
5.5
通讯作者：
N. Penfold;Jessica R. Whatley;S. Armes
中科院分区：
文献类型：
--
作者：
N. Penfold;Jessica R. Whatley;S. Armes
合成了两种平均聚合度分别为45和113的三硫代碳酸酯基聚乙二醇（PEG）大分子链转移剂（macro-CTA），其末端官能度≥94%。然后，这些PEG-三硫代碳酸酯大分子CTA的二元混合物通过甲基丙烯酸2-羟丙酯（HPMA）的可逆加成-断裂链转移（RAFT）水分散体聚合进行扩链。PEG 45和PEG 113大分子CTA的相对比例和PHPMA核形成嵌段的聚合度的系统变化导致形成[x PEG 45 + z PEG 113] - PHPMAn嵌段共聚物球、蠕虫或囊泡，其中x和z分别表示PEG 45和PEG 113的摩尔分数。构建相图以建立嵌段共聚物组成与纳米颗粒形态之间的关系。通过目视检查、动态光散射、透射电子显微镜和透射电子显微镜等方法对嵌段共聚物蠕虫的温敏行为进行了评价。
Two trithiocarbonate-based poly(ethylene glycol) (PEG) macromolecular chain transfer agents (macro-CTAs) with mean degrees of polymerization of 45 and 113 were prepared with ≥94% chain-end functionality. Binary mixtures of these PEG–trithiocarbonate macro-CTAs were then chain-extended via reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion polymerization of 2-hydroxypropyl methacrylate (HPMA). Systematic variation of the relative proportions of PEG45 and PEG113 macro-CTAs and the degree of polymerization of the PHPMA core-forming block resulted in the formation of [x PEG45 + z PEG113] – PHPMAn block copolymer spheres, worms, or vesicles, where x and z represent the mole fractions of PEG45 and PEG113, respectively. A phase diagram was constructed to establish the relationship between block copolymer composition and nanoparticle morphology. The thermoresponsive behavior of block copolymer worms was assessed by visual inspection, dynamic light scattering (DLS), transmission electron mi...