Using click chemistry to dial up the modulus of doubly crosslinked microgels through precise control of microgel building block functionalisation
Using click chemistry to dial up the modulus of doubly crosslinked microgels through precise control of microgel building block functionalisation
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使用点击化学通过精确控制微凝胶构建块功能化来提高双交联微凝胶的模量
DOI：
10.1039/c4py01753f
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发表时间：
2015
影响因子：
4.6
通讯作者：
Farley R
中科院分区：
文献类型：
--
作者：
Farley R
双交联型微凝胶(DX MG)是由共价交联的乙烯基官能化微凝胶粒子构成的水凝胶。到目前为止，还不可能精确地控制微凝胶(MG)颗粒的乙烯基官能化程度，微凝胶(MG)颗粒充当水凝胶组装的胶体构件。此外，到目前为止，DX MG的准备范围并不大。这项研究通过构建一类新的DX MG来解决这两个挑战，该MG粒子通过铜催化的叠氮烯基环加成(CuAAC)来实现乙烯基官能化。本文制备了聚(2-乙烯基吡啶-丙烯酸丙酯)(PVP-PA)微球，并用甲基丙烯酸叠氮丙酯(AZPMA)对其进行了乙烯基官能化处理，得到了PVP-Pax-PMAy微球。乙烯基官能团化程度(Y)的值以精确控制的方式从0到7.0mol%变化。当pH值小于或等于3.0时，浓缩分散体从流体转变为物理凝胶，并通过相邻粒子的乙烯基团的自由基偶联以共价互连的方式得到PVP-Pax-PMAy DX MG。DX MG的存储模数随MG浓度和y的值呈线性变化。这里研究的新型DX MG不仅能够精确控制MG的官能化和DX MG的机械性能，而且它们还显示出胶体结晶性的证据，这可能导致未来的光子凝胶应用。我们基于CuAAC的方法应该是多才多艺的，并有望使一系列新的DX MG得以制备。
Doubly crosslinked microgels (DX MGs) are hydrogels constructed by covalently interlinked vinyl-functionalised microgel particles. Until now it has not been possible to precisely control the extent of vinyl functionalisation of the microgel (MG) particles which act as the colloidal building blocks for hydrogel assembly. Furthermore, the range of DX MGs prepared to date has been modest. This study addresses both of these challenges by constructing a new class of DX MG using MG particles that were vinyl functionalised by copper catalysed azide–alkyne cycloaddition (CuAAC). Here, poly(2-vinylpyridine-co-propargyl acrylate) (PVP-PA) MG particles were prepared and vinyl functionalised by CuAAC using azidopropyl methacrylate (AZPMA) to give PVP-PAx–PMAy MGs. Values for the extent of vinyl functionalisation (y) were varied from 0 to 7.0 mol% in a precisely controlled manner. Concentrated dispersions were transformed from fluids to physical gels at pH values of less than or equal to 3.0 and covalently inter-linked to give PVP-PAx–PMAy DX MGs by free-radical coupling of the vinyl groups of neighbouring particles. The storage modulus of the DX MGs varied linearly with both MG concentration and the value for y. Not only did the new DX MGs studied here enable precise control of MG functionalisation and DX MG mechanical properties, they also showed evidence of colloidal crystallinity which may lead to future photonic gel applications. Our CuAAC-based approach should be versatile and is expected to enable a range of new DX MGs to be prepared.
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软微水凝胶颗粒高密度悬浮液屈服行为的简单特征。
影响因子：
3.4
作者：
K. Urayama;Taku Saeki;Shengquan Cong;Shota Uratani;T. Takigawa;Masaki Murai;D. Suzuki
通讯作者：
D. Suzuki
影响因子：
5.5
作者：
Sakai, Takamasa;Matsunaga, Takuro;Chung, Ung-il
通讯作者：
Chung, Ung-il
影响因子：
4.9
作者：
Malkoch, Michael;Vestberg, Robert;Hawker, Craig J.
通讯作者：
Hawker, Craig J.
影响因子：
4.6
作者：
Farley, Robert;Saunders, Brian R.
通讯作者：
Saunders, Brian R.
影响因子：
62.1
作者：
Iha RK;Wooley KL;Nyström AM;Burke DJ;Kade MJ;Hawker CJ
通讯作者：
Hawker CJ