Devaux C, Chapel J P, Beyou E, Chaumont Ph
Laboratoire des Matériaux Polymères et Biomatériaux - UMR CNRS 5627, Blg. ISTIL Université Claude Bernard Lyon I, 43, bd. du 11 novembre 1918, 69622 Villeurbanne Cedex, France, Villeurbanne Cedex, France.
Eur Phys J E Soft Matter. 2002 Apr;7(4):345-52. doi: 10.1140/epje/i2001-10098-2.
Thin layers of polystyrene were grown from surface-grafted nitroxide initiators via controlled "living" free radical polymerization. The "reactive" Langmuir-Blodgett deposition method allowed an effective control of the initiator layer density leading to PS brushes with different and high grafting density and stretching. The influence of the grafting density on the layer structure was studied. Comparison with theoretical predictions for monodispersed brushes in bad solvent was discussed. The thickness was found to vary linearly with molecular weight and the density dependence was shown using wetting measurements. Special features of controlled radical nitroxide polymerization from a surface were discussed. A direct comparison of the molecular weight and polydispersity between surface and bulk polymers was made by de-grafting the brushes into a toluene/HF solution. Finally, some evidence of a "surface Fischer" effect was shown from re-initiated layers.
通过可控的“活性”自由基聚合反应，从表面接枝的氮氧化物引发剂生长出聚苯乙烯薄层。“反应性”朗缪尔-布洛杰特沉积方法能够有效控制引发剂层密度，从而得到具有不同且高接枝密度和伸展度的聚苯乙烯刷。研究了接枝密度对层结构的影响。讨论了与不良溶剂中单分散刷的理论预测的比较。发现厚度随分子量呈线性变化，并通过润湿性测量显示了密度依赖性。讨论了从表面进行可控自由基氮氧化物聚合的特殊特征。通过将刷状物解枝到甲苯/氢氟酸溶液中，对表面聚合物和本体聚合物之间的分子量和多分散性进行了直接比较。最后，从再引发层显示了一些“表面费舍尔”效应的证据。
