Rusen Edina, Mocanu Alexandra, Brincoveanu Oana, Toader Gabriela, Gavrila Raluca, Diacon Aurel, Stavarache Cristina
Faculty of Chemical Engineering and Biotechnologies, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania.
National Institute for Research and Development in Microtechnologies-IMT Bucharest, 126A Erou Iancu Nicolae Street, Bucharest 077190, Romania.
ACS Omega. 2024 Sep 29;9(41):42455-42469. doi: 10.1021/acsomega.4c06179. eCollection 2024 Oct 15.
This study presents for the first time the polymerization of methyl methacrylate (MMA) in the presence of poly(vinyl chloride) (PVC) that takes place by both SARA-ATRP and SET-LRP mechanisms. The two types of polymerizations that occur in the system are PMMA grafting to the PVC backbone and the formation of a new PMMA polymer, both occurring in the presence of a Cuwire. The polymerizations were controlled as confirmed by the molecular weight evolution, polymerization kinetics, and variations in the dispersity value. The MMA polymerization in the presence of PVC at 60 and 70 °C leads to the formation of two polymer species characterized by an increase in the molecular weight with the conversion and a narrowing of the dispersity value with the reaction progress. To increase the degree of control over the polymerization, the same reaction was performed at room temperature, which allowed us to highlight the presence of the SARA-ATRP and SET-LRP mechanisms via subsequent polymer chain extensions. The results demonstrated that PMMA grafting on PVC polymers follows a SARA-ATRP mechanism, while the formation of a PMMA homopolymer entails a SET-LRP process. The influence of solvent nature on the polymerization reaction was studied by performing the grafting of -isopropylacrylamide (NIPAM) onto the surface of PVC particles in aqueous media in the presence and in the absence of CuCl. The polymerization reactions and the obtained materials were studied by gel permeation chromatography (GPC), H NMR, DMA, scanning electron microscopy (SEM), and atomic force microscopy (AFM).
本研究首次展示了甲基丙烯酸甲酯（MMA）在聚氯乙烯（PVC）存在下通过SARA-ATRP和SET-LRP机制进行的聚合反应。体系中发生的两种聚合反应分别是PMMA接枝到PVC主链上以及形成新的PMMA聚合物，这两种反应均在铜丝存在的情况下发生。通过分子量变化、聚合动力学以及分散度值的变化证实了聚合反应是可控的。在60℃和70℃下，MMA在PVC存在下的聚合反应导致形成两种聚合物，其特点是分子量随转化率增加，分散度值随反应进行而变窄。为了提高对聚合反应的控制程度，在室温下进行了相同的反应，这使我们能够通过后续的聚合物链延伸突出SARA-ATRP和SET-LRP机制的存在。结果表明，PVC聚合物上的PMMA接枝遵循SARA-ATRP机制，而PMMA均聚物的形成则需要SET-LRP过程。通过在有和没有CuCl的情况下在水性介质中进行N-异丙基丙烯酰胺（NIPAM）在PVC颗粒表面的接枝，研究了溶剂性质对聚合反应的影响。通过凝胶渗透色谱（GPC）、核磁共振氢谱（¹H NMR）、动态热机械分析（DMA）、扫描电子显微镜（SEM）和原子力显微镜（AFM）对聚合反应和所得材料进行了研究。
