Falireas Panagiotis G, Ameduri Bruno
ICGM, Univ. Montpellier, CNRS, ENSCM, 34095 Montpellier, France.
Polymers (Basel). 2021 Aug 11;13(16):2676. doi: 10.3390/polym13162676.
New copolymers based on vinylidene fluoride (VDF) and 2,3,3,3-tetrafluoroprop-1-ene (1234yf) were synthesized by organometallic-mediated radical copolymerization (OMRcP) using the combination of bis(-butylcyclohexyl) peroxydicarbonate initiator and bis(acetylacetonato)cobalt(II), (Co(acac)) as a controlling agent. Kinetics studies of the copolymerization of the fluoroalkenes copolymers were monitored by GPC and F NMR with molar masses up to 12,200 g/mol and dispersities () ranging from 1.33 to 1.47. Such an OMRcP behaves as a controlled copolymerization, evidenced by the molar mass of the resulting copolymer-monomer conversion linear relationship. The reactivity ratios, r, of both comonomers were determined by using the Fineman-Ross and Kelen-Tüdos fitting model leading to r = 0.384 ± 0.013 and r = 2.147 ± 0.129 at 60 °C, showing that a lower reactivity of VDF integrated in the copolymer to a greater extent leads to the production of gradient or pseudo-diblock copolymers. In addition, the Q (0.03) and e (0.06 and 0.94) parameters were assessed, as well as the dyad statistic distributions and mean square sequence lengths of PVDF and P1234yf.
通过有机金属介导的自由基共聚(OMRcP),使用双(-丁基环己基)过氧二碳酸酯引发剂和双(乙酰丙酮)钴(II)(Co(acac))作为控制剂,合成了基于偏二氟乙烯(VDF)和2,3,3,3-四氟丙烯(1234yf)的新型共聚物。通过凝胶渗透色谱(GPC)和氟核磁共振(F NMR)监测氟烯烃共聚物的共聚动力学,所得共聚物的摩尔质量高达12,200 g/mol,分散度()在1.33至1.47之间。这种OMRcP表现为可控共聚,所得共聚物的摩尔质量与单体转化率呈线性关系证明了这一点。通过使用Fineman-Ross和Kelen-Tüdos拟合模型确定两种共聚单体的竞聚率r,在60°C时r = 0.384 ± 0.013和r = 2.147 ± 0.129,表明共聚物中整合的VDF反应活性较低,在更大程度上导致了梯度或准二嵌段共聚物的产生。此外,还评估了Q(0.03)和e(0.06和0.94)参数,以及聚偏二氟乙烯(PVDF)和聚1234yf的二元统计分布和均方序列长度。