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可逆络合聚合制备含悬垂双键超支化聚合物
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作者 杨宏军 任子叶 +5 位作者 宋肄业 黄文艳 薛小强 蒋其民 江力 蒋必彪 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第2期7-11,共5页
在偶氮二异庚腈(V65)引发甲基丙烯酸烯丙酯(AMA)的传统自由基聚合体系中加入少量碘单质(I2)和碘化钠(NaI)就成功实现了AMA的"活性"/可控聚合,一步法制备了含大量悬垂双键的超支化聚合物。通过核磁共振(NMR)和三检测凝胶渗透色... 在偶氮二异庚腈(V65)引发甲基丙烯酸烯丙酯(AMA)的传统自由基聚合体系中加入少量碘单质(I2)和碘化钠(NaI)就成功实现了AMA的"活性"/可控聚合,一步法制备了含大量悬垂双键的超支化聚合物。通过核磁共振(NMR)和三检测凝胶渗透色谱(TD-GPC)对所得聚合物的结构和聚合反应过程进行了分析和表征。结果表明,在此体系中AMA的转化率为81.9%时无交联反应发生,所得超支化聚合物数均相对分子质量为1.11×104,相对分子质量分布为6.62,其特性黏数和流体力学半径均小于相同相对分子质量的线型聚合物,具有明显的支化结构。在聚合反应过程中,单体转化率与反应时间呈一级动力学规律,具有典型的活性聚合特征。 展开更多
关键词 超支化聚合物 悬垂双键 可逆络合聚合 甲基丙烯酸烯丙酯
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Piezoelectrically Mediated Reactions:From Catalytic Reactions to Organic Transformations
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作者 ziye ren Yuhao Peng +4 位作者 Hanliang He Chengqiang Ding Jialin Wang Zhao Wang Zhengbiao Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第1期111-128,共18页
Recently,piezocatalysis has attracted considerable attention as a new type of renewable mechanical energy conversion technology,which relies on the strain induced polarization of the piezoelectric material.This new te... Recently,piezocatalysis has attracted considerable attention as a new type of renewable mechanical energy conversion technology,which relies on the strain induced polarization of the piezoelectric material.This new technology has been extensively applied in the applications of water splitting,water remediation,gas purification and tumor therapy.Despite the rapid development in the piezo-catalysis,the utilization of piezoelectric materials for synthetic purpose is still under exploration.Piezoelectric means to promote or-ganic reactions expand the scope of piezoelectrically mediated reactions and show successes in both organic and polymer synthesis.Herein,we provide a comprehensive review on recent progress of piezoelectrically mediated reactions,catalytic mechanisms and applications in the last few years.The limitations and future directions of this area are also discussed.We believe this review will provide new insights into the underlying mechanism of piezoelectric mediated electron transfer process and guide the design of new chemistry. 展开更多
关键词 Piezocatalysis Heterogeneous catalysis Mechanical energy POLYMERIZATION Organic synthesis Water spilling Tumor therapy Mechanoredox Piezoelectric material
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Piezoelectric Zinc Oxides with High Polar Facets Ratios for Mechanically Controlled RAFT Polymerization
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作者 Chengqiang Ding ziye ren +5 位作者 Jian Wang Longfei Zhang Yuhan Yan Danming Wu Zhao Wang Zhengbiao Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第20期2691-2696,共6页
Mechanoredox chemistry that uses highly polarized piezoelectric materials as mechanoredox catalysts to promote redox reactions has emerged recently.It provides an alternative approach alongside the existing polymeriza... Mechanoredox chemistry that uses highly polarized piezoelectric materials as mechanoredox catalysts to promote redox reactions has emerged recently.It provides an alternative approach alongside the existing polymerization methods.Despite recent accomplishments,determining the quantitative relationship between the structure of ZnO and its catalytic performance for polymerization is still challenging.Herein,we prepared various ZnO crystals with different polar facets ratios to achieve efficient mechanically induced reversible addition-fragmentation chain transfer polymerization(mechano-RAFT).ZnO prepared from Zn(NO3)2 showed a high polar facet ratio of 1.66 and offered the highest catalytic activity among all ZnO samples.A near-quantitative initiator efficiency of 99.5%and narrow molecular weight distribution were achieved for the polymerization of n-butyl acrylate.Furthermore,the high chain-end fidelity and chain extension capability were also evidenced by MALDI-TOF MS and GPC analysis.This work highlighted the significant contribution of polar facets in ZnO to its catalytic activity and will guide the design of mechanoredox catalysis with superior catalytic performance in the future. 展开更多
关键词 Mechanoredox chemistry Catalytic activity ZnO crystals RAFT polymerization
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