POLYMERS FOR ADVANCED TECHNOLOGIES
·
2021
·Vol. 32
·期 6
·2452-2464
·
IF 3.665
Binglin Wang,Jiaxin Li,Xuejun Lai,Hongqiang Li,Yishen Chen,Xingrong Zeng
Endowing intumescent flame retardant (IFR) with free-radical quenching capability is a promising method to improve its efficiency. Herein, a novel N -alkoxyamine containing macromolecular intumescent flame retardant (RQMIFR) was synthesized via nucleophilic substitution reaction and combined with ammonium polyphosphate (APP) to improve the thermostability and fire resistance of polypropylene (PP). The results showed that there was a good synergism between RQMIFR and APP, which effectively enhanced the thermostability and flame retardancy of PP. When the content of RQMIFR was 8.33 wt% and APP was 16.67 wt%, the limiting oxygen index of PP increased from 19.0% to 39.5% and achieved a UL-94 V-0 rating. Besides, the peak heat release rate, total heat release, carbon monoxide production, and carbon dioxide production were remarkably reduced. It was revealed that during combustion, RQMIFR generated nitroxyl free-radicals and quenched the active free radicals produced by PP both in gas and condensed phase. Simultaneously, RQMIFR and APP worked synergistically to form a compact intumescent char layer through the esterification, cross-linking, cyclization, and foaming reactions, thus effectively improved the thermostability and flame retardancy of PP.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2016
·Vol. 8
·期 3
·74
·
IF 2.944
Meng Yu,Yi Di,Ying Zhang,Yuting Zhang,Jia Guo,Haojie Lu,Changchun Wang
As a facile method to prepare hydrophilic polymeric microspheres, reflux precipitation polymerization has been widely used for preparation of polymer nanogels. In this article, we synthesized a phthalamide-protectedN-aminooxy methyl acrylamide (NAMAm-p) for preparation of alkoxyamine-functionalized polymer composite microspheres via reflux precipitation polymerization. The particle size and functional group density of the composite microspheres could be adjusted by copolymerization with the second monomers,N-isopropyl acrylamide, acrylic acid or 2-hydroxyethyl methacrylate. The resultant microspheres have been characterized by TEM, FT-IR, TGA and DLS. The experimental results showed that the alkoxyamine group density of the microspheres could reach as high as 1.49 mmol/g, and these groups showed a great reactivity with ketone/aldehyde compounds. With the aid of magnetic core, the hybrid microspheres could capture and magnetically isolate glycopeptides from the digested mixture of glycopeptides and non-glycopeptides at a 1:100 molar ratio. After that, we applied the composite microspheres to profile the glycol-proteome of a normal human serum sample, 95 unique glycopeptides and 64 glycoproteins were identified with these enrichment substrates in a 5 μL of serum sample.Keywords:alkoxyamine-functionalized microspheres;reflux precipitation polymerization;magnetic composite microspheres;oxime click;glycoproteins/glycopeptides enrichment
研究领域:
生物化学
·
蛋白质组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Xiaoguang Qiao,Xin Dong,Ge shi,Yanjie He,Xinchang Pang
Nitroxide-mediated polymerization (NMP) is known to be a simple reversible deactivation radical polymerization (RDRP) method for preparing well defined polymers. In compared with other RDRP methods, NMP was highlighted by the clean and low toxic product which is favorable for some sensitive biological and electronic applications. Here we reported the first case of oxygen tolerance nitroxide-mediated miniemulsion polymerization, by introducing glucose oxidase (GOx) and ascorbic acid (AsAc) to the system. Without degassing treatment, the miniemulsion polymerization can be carried on using alkoxyamine 3-(((2-cyanopropan-2-yl)oxy) (cyclohexyl)amino)-2,2-dimethyl-3-phenylpropanenitrile (Dispolreg 007) as the initiator. The oxygen tolerance NMP miniemulsion exhibited similar living and control behavior to the degassing system, and the chain extension could also be performed without degassing. The characteristics of this enzyme assisted oxygen tolerant heterogeneous NMP may provide exciting new opportunities for increased versatility of NMP polymerization in preparation of polymeric nano-objects.
研究领域:
高分子化学
·
材料科学
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
Polymer Chemistry
·
2020
·Vol. 12
·期 4
·526-533
·
IF 5.342
Huanhuan Ma,Linan Wang,Yachao Liang,Zhe Cui,Peng Fu,Minying Liu,Xiaoguang Qiao,Xinchang Pang
Tetraphenylethylene (TPE)-containing 4-amino-2,2,6,6-tetramethylpiperidine-1-oxyl (NH2-TEMPO) and 3-(((2-cyanopropan-2-yl)oxy)(cyclohexyl)amino)-2,2-dimethyl-3-phenylpropanenitrile (Dispolreg 007) were synthesized and utilized to mediate/initiate NMP in both homogeneous and heterogeneous polymerization systems. The introduction of TPE groups decreased the C–O bond dissociation energy (BDE) of NH2-TEMPO-St and led to more efficient NMP with a higher reaction rate, even at lower temperatures. Moreover, for both solution polymerization and miniemulsion polymerization, quantitative information of the polymerization process could be easily acquired with the naked eye without destroying the reaction system, by building the relationship between the increased photoluminescence (PL) intensity of the system and monomer conversion as well as the molecular weight (Mn).
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）