Preparation of Narrowly Distributed Stable and Soluble Polyacetylene Block Copolymer Nanoparticles
Preparation of Narrowly Distributed Stable and Soluble Polyacetylene Block Copolymer Nanoparticles
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DOI：
10.1021/ja983587e
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发表时间：
1999-02
影响因子：
15
通讯作者：
Chi Wu;A. Niu;L. Leung;T. Lam
中科院分区：
文献类型：
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作者：
Chi Wu;A. Niu;L. Leung;T. Lam
四十年前，Natta 等人首次发现了黑色粉末状的聚乙炔 (PA)。 1 二十年后，Chiang 等人2 发现掺杂的 PA 薄膜具有接近金属的导电率。作为一种潜在的导电和非线性光学材料，聚乙炔在过去二十年中得到了广泛的研究。 3 然而，聚乙炔非常棘手，以至于其许多潜在应用受到阻碍。对聚乙炔进行改性，使其能够加工成不同的实际组件用于实际应用，一直是该领域的一个长期梦想。另一方面，广泛的研究表明，如果可以使其中一个嵌段不溶，嵌段和接枝共聚物可以在溶液中形成聚合物胶束。 4-9 人们普遍认为二嵌段共聚物胶束具有核壳纳米结构，以不溶性嵌段为核心，可溶性嵌段为溶胀壳，类似于小分子表面活性剂胶束。通常，通过将共聚物溶液缓慢添加到聚合物嵌段之一的非溶剂中来改变溶剂质量。对于水溶性嵌段共聚物，如果嵌段之一可以在较高温度下从亲水性变为疏水性，则还可以改变溶液温度以诱导胶束形成。 10 请注意，胶束的形成是热力学驱动的，并且该过程在稀溶液中通常非常快，以至于观察起来很困难，甚至不可能。据我们所知，形成动力学尚未有报道。最近，梁等人。 11报道称，聚（苯基乙烯基亚砜）（PVSO）在加热时可以缓慢转化为聚乙炔。研究了PVSO本体热解前后的形貌和电学性质以及溶液中的热解动力学和光学性质。 11-13日
Forty years ago, polyacetylene (PA) as a black powder was first discovered by Natta et al. 1 Twenty years later, Chiang et al.2 found that the doped PA film had a conductivity close to metal. As a potential conducting and nonlinear optical material, polyacetylene has been extensively studied in the last two decades. 3 However, polyacetylene is so intractable that its many potential applications have been hindered. It has been a long dream in the field to modify polyacetylene so that it could be processed into different real components for real applications. On the other hand, extensive studies showed that block and graft copolymers could form polymeric micelles in solution if one could make one of the blocks insoluble. 4-9 It is generally accepted that diblock copolymeric micelles have a core -shell nanostructure with the insoluble block as the core and the soluble block as the swollen shell, resembling small molecule surfactant micelles. Normally, the solvent quality was varied by slowly adding a copolymer solution into a nonsolvent for one of the polymer blocks. For water-soluble block copolymers, one could also vary the solution temperature to induce the micelle formation if one of the blocks could change from hydrophilic to hydrophobic at higher temperatures. 10 Note that the micelle formation is thermodynamically driven and the process is usually so fast in dilute solution that its observation is difficult, if not impossible. To our knowledge, the formation kinetics has not yet been reported. Recently, Leung et al. 11 reported that poly(phenyl vinyl sulfoxide) (PVSO) could be slowly converted into polyacetylene upon heating. The morphology and the electrical properties of PVSO before and after thermolysis in bulk and its thermolysis kinetics and optical properties in solution have been studied. 11-13