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N⁃苯基马来酰亚胺共聚物的合成及对PVC树脂耐热改性效果研究
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作者 孙芳芳 宋运运 《中国塑料》 CAS CSCD 北大核心 2024年第7期49-54,共6页
通过种子乳液聚合结合半连续加料方式,成功聚合出分子结构一致且与聚氯乙烯(PVC)树脂具有良好相容性的聚(N‐苯基马来酰亚胺‐苯乙烯‐丙烯腈)(PNSA)共聚物胶乳,将其与PVC树脂直接复合制备PNSA/PVC复合材料,并对PNAS耐热改性的效果进行... 通过种子乳液聚合结合半连续加料方式,成功聚合出分子结构一致且与聚氯乙烯(PVC)树脂具有良好相容性的聚(N‐苯基马来酰亚胺‐苯乙烯‐丙烯腈)(PNSA)共聚物胶乳,将其与PVC树脂直接复合制备PNSA/PVC复合材料,并对PNAS耐热改性的效果进行评价。结果表明,PNSA纳米胶乳颗粒粒径在155.3~251.5 nm之间,粒径分布均一;PNSA共聚物分子组成呈无规结构,分子结构一致,差示扫描量热曲线呈现单一的玻璃化转变温度(T_(g)),且与PVC树脂具有极佳的相容性;PNSA含量由0升高至50%(质量比,下同)时,复合材料的T_(g)由84.8℃提高到107.2℃,提高了22.4℃,维卡软化温度由71.2℃提高到91.9℃,提高了20.7℃;除耐热性改善以外,复合材料的力学性能也有一定程度的提高,本文的研究有利于PVC应用领域的进一步拓展。 展开更多
关键词 聚氯乙烯 n‐苯基马来酰亚胺 自由基共聚 种子乳液 耐热改性
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偶氮苯基小分子光控聚N-异丙基丙烯酰胺在离子液体中的自组装
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作者 李佩琪 王彩虹 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第2期32-38,共7页
偶氮苯基材料因其具有可逆的光致顺反异构特性,可调控聚合物的自组装行为而受到广泛关注。采用不同结构且广泛商业化的偶氮苯基小分子(偶氮苯(AZO)、对羟基偶氮苯(AZO-OH)、对氨基偶氮苯(AZO-NH2)、二甲基黄[AZO-N(CH_(3))_(2)])作为光... 偶氮苯基材料因其具有可逆的光致顺反异构特性,可调控聚合物的自组装行为而受到广泛关注。采用不同结构且广泛商业化的偶氮苯基小分子(偶氮苯(AZO)、对羟基偶氮苯(AZO-OH)、对氨基偶氮苯(AZO-NH2)、二甲基黄[AZO-N(CH_(3))_(2)])作为光分子开关,控制聚N-异丙基丙烯酰胺(PNIPAm)在1-乙基-3-甲基咪唑双(三氟甲基磺酰基)亚胺([C2mim][NTf_(2)])离子液体中的自组装行为,探讨不同偶氮苯基末端基元对于PNIPAm自组装相行为的影响。结果表明,偶氮苯基小分子均能有效调控PNIPAm在[C2mim][NTf_(2)]离子液体中的相变响应行为,但不同的末端基元对于PNIPAm的相变温度及相变区间影响甚微。结合原位变温红外谱图分析可知,紫外光照强化了PNIPAm与离子液体之间的相互作用,从而抑制了PNIPAm侧链间的相互聚集,这将促进紫外光照条件下“溶剂化”效应的发生,可获得更低的相变温度。 展开更多
关键词 偶氮苯 n-异丙基丙烯酰胺 离子液体 自组装 分子开关 相变 响应行为
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基于n型柔性半导体的有机晶体管及其电子-离子双响应特性
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作者 蒋浩 钟岳桁 +1 位作者 王刚 王宏志 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第1期39-44,共6页
为了研究n型有机混合离子电子导体电子-离子双响应特性及分子量对载流子迁移率的影响,采用具有平面刚性的梯形分子链结构的高分子量聚苯并二咪唑苯并菲绕啉二酮制备高性能有机电化学晶体管,并对晶体管紫外可见吸收光谱和晶体管器件电气... 为了研究n型有机混合离子电子导体电子-离子双响应特性及分子量对载流子迁移率的影响,采用具有平面刚性的梯形分子链结构的高分子量聚苯并二咪唑苯并菲绕啉二酮制备高性能有机电化学晶体管,并对晶体管紫外可见吸收光谱和晶体管器件电气性能进行表征。结果表明,利用高分子量聚苯并二咪唑苯并菲绕啉二酮制备的n型有机电化学晶体管表现出极高的响应速度(0.034 s)、高载流子迁移率(4.72×10^(-3) cm^(2)/(V·s)),以及在水系电解液中优异的稳定性(稳定运行超过120次脉冲循环)。 展开更多
关键词 有机晶体管 n型柔性半导体 电子-离子双响应特性 聚苯并二咪唑苯并菲绕啉二酮 载流子迁移率
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PNIPAm@CMCS生物基水凝胶吸附染料研究
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作者 梅江洋 金勇 +3 位作者 陈浩楠 周荣 黄琨 毛喆贤 《中国皮革》 CAS 2024年第10期1-6,共6页
针对目前皮革废水处理剂难回收问题,以羧甲基壳聚糖(CMCS)和聚N-异丙基丙烯酰胺(PNIPAm)为原料,合成一种兼具优异吸附性和可重复利用且易回收的生物基水凝胶(PNIPAm@CMCS),并对该水凝胶的抗疲、亲水、溶胀、吸附及抗菌等性能进行了研究... 针对目前皮革废水处理剂难回收问题,以羧甲基壳聚糖(CMCS)和聚N-异丙基丙烯酰胺(PNIPAm)为原料,合成一种兼具优异吸附性和可重复利用且易回收的生物基水凝胶(PNIPAm@CMCS),并对该水凝胶的抗疲、亲水、溶胀、吸附及抗菌等性能进行了研究。结果表明,所制备的生物基水凝胶具有出色的抗疲性(耐循环压缩15次)、溶胀率(2034%)、吸附性(伊红Y=587 mg/g,罗丹明=444 mg/g,甲基橙=621 mg/g)和抗菌性能(抗菌率=100%)。该生物基水凝胶作为一类高效、环保的染料废水处理剂,展现了广阔的应用前景,有望为制革工业处理含染料污水提供新的思路。 展开更多
关键词 n-异丙基丙烯酰胺 羧甲基壳聚糖 水凝胶 染料 制革工艺污水处理
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智能窗口用热响应聚(N-异丙基丙烯酰胺)水凝胶的研究进展
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作者 陈冠桦 程欣瑶 +3 位作者 翟迅 段文皓 王润东 于环洋 《化工技术与开发》 CAS 2024年第4期46-49,共4页
本文综述了智能窗口用热响应聚(N-异丙基丙烯酰胺)水凝胶的热响应机理,介绍了该水凝胶材料的制备方法及相关的性能,阐述了影响PTC效应的主要因素及提高其稳定性的方法,展望了智能窗口用热响应聚(N-异丙基丙烯酰胺)水凝胶未来的研究方向... 本文综述了智能窗口用热响应聚(N-异丙基丙烯酰胺)水凝胶的热响应机理,介绍了该水凝胶材料的制备方法及相关的性能,阐述了影响PTC效应的主要因素及提高其稳定性的方法,展望了智能窗口用热响应聚(N-异丙基丙烯酰胺)水凝胶未来的研究方向和发展前景。 展开更多
关键词 n-异丙基丙烯酰胺 水凝胶 智能窗口
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聚N-异丙基丙烯酰胺/聚丙烯酸水凝胶的制备及性能研究
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作者 吴英 王书芳 +1 位作者 李雨露 戴杨雷 《山东化工》 CAS 2024年第1期38-41,共4页
当外界环境发生变化时,环境敏感型水凝胶的物理性质或化学性质会随之发生改变,大部分水凝胶对环境的响应比较单一。以丙烯酸(AA)和N-异丙基丙烯酰胺(NIPAm)为原料制备的聚N-异丙基丙烯酰胺/聚丙烯酸水凝胶既可以对温度变化也可以对pH值... 当外界环境发生变化时,环境敏感型水凝胶的物理性质或化学性质会随之发生改变,大部分水凝胶对环境的响应比较单一。以丙烯酸(AA)和N-异丙基丙烯酰胺(NIPAm)为原料制备的聚N-异丙基丙烯酰胺/聚丙烯酸水凝胶既可以对温度变化也可以对pH值变化做出响应。实验采用一锅法制备了聚N-异丙基丙烯酰胺/聚丙烯酸水凝胶,通过调节丙烯酸的中和度、丙烯酸(AA)和N-异丙基丙烯酰胺(NIPAm)两种单体的配比、交联剂N,N′-亚甲基双丙烯酰(BIS)和引发剂过硫酸钾(KPS)的用量,研究其对水凝胶的吸水性能、拉伸性能的影响,并考察了所制备的聚N-异丙基丙烯酰胺/聚丙烯酸水凝胶对温度及pH响应性能。实验结果表明:当丙烯酸的中和度为125%、n(NIPAm)∶n(AA)=0.3∶1、BIS的质量分数为0.5%、KPS的质量分数为1%时,制备的水凝胶溶胀率最大且有一定的弹性,室温下吸水率达179.73 g/g。该水凝胶在酸性缓冲溶液(pH值=3)中收缩,当缓冲溶液的pH值大于3,水凝胶发生溶胀,具有灵敏可逆的pH响应性能,同时该水凝胶兼具热缩温敏性能。 展开更多
关键词 聚丙烯酸 n-异丙基丙烯酰胺 水凝胶 PH值
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含PNIPAM嵌段有机纳米管的合成及其对MB与ARS的吸附与释放性能探究
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作者 王卓玉 施卜银 《宁夏工程技术》 CAS 2024年第2期124-131,共8页
为了高效吸附染料废水中的染料分子,制备了一种具有温度可控性的新型吸附材料。首先,采用可控自由基聚合和开环聚合将聚N-异丙基丙烯酰胺(PNIPAM)引入多孔有机纳米管中,制备了具有核壳结构的多组分聚合物分子刷;其次,利用分子刷嵌段聚... 为了高效吸附染料废水中的染料分子,制备了一种具有温度可控性的新型吸附材料。首先,采用可控自由基聚合和开环聚合将聚N-异丙基丙烯酰胺(PNIPAM)引入多孔有机纳米管中,制备了具有核壳结构的多组分聚合物分子刷;其次,利用分子刷嵌段聚合物的傅克烷基化超交联过程生成了具有微孔、中孔和大孔结构的PNIPAM修饰的多级孔有机纳米管网络(MONNs)聚合物;最后,探究了MONNs对染料分子亚甲基蓝(MB)、茜素红S(ARS)的吸附与释放性能。结果表明,该方法制备的MONNs材料对染料分子具有良好的吸附效果。 展开更多
关键词 n-异丙基丙烯酰胺 多级孔有机纳米管网络 吸附与释放性能 染料废水处理
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利用NVP组分调控亲水增强型温敏性PNIPAAm共聚物
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作者 范晓光 雷景胜 +3 位作者 顾诗雅 冷旭 刘畅 杨磊 《材料导报》 CSCD 北大核心 2023年第15期230-236,共7页
聚N-异丙基丙烯酰胺(PNIPAAm)是目前在生物医药领域研究和应用最为广泛的一种温敏性聚合物。但PNIPAAm均聚物的温敏性能相对单一,且由其构建的终产物难以在较宽温度范围内通过改变温度发生整体体积或表面润湿性能转变,因此限制了其应用... 聚N-异丙基丙烯酰胺(PNIPAAm)是目前在生物医药领域研究和应用最为广泛的一种温敏性聚合物。但PNIPAAm均聚物的温敏性能相对单一,且由其构建的终产物难以在较宽温度范围内通过改变温度发生整体体积或表面润湿性能转变,因此限制了其应用范围。为了扩展PNIPAAm的应用领域,设计可以调控特别是提升PNIPAAm基材最低临界溶液温度(LCST)的温敏性聚合物十分必要。鉴于此,本研究将亲水性N-乙烯基吡咯烷酮(NVP)引入温敏性聚合物分子骨架,同时利用共聚物的反应基团将P(NIPAAm-co-NVP)共聚物聚合接枝于铂片表面从而形成共聚物膜。衰减全反射-傅里叶变换红外光谱(ATR-FTIR)、核磁共振氢谱(1H-NMR)和凝胶渗透色谱(GPC)的鉴定结果表明各单体间的共聚反应均按预定方案进行,且可显著提升NVP在聚合过程的参与率;动态光散射(DLS)和静态接触角数据、扫描电子显微镜(SEM)图像均证明可以利用NVP组分提升P(NIPAAm-co-NVP)共聚物的LCST,从而获得亲水增强型的温敏性共聚物膜,该膜可用于药物控制释放和非侵害性细胞收获等。 展开更多
关键词 n-异丙基丙烯酰胺(PnIPAAm) n-乙烯基吡咯烷酮(nVP) 最低临界溶液温度(LCST) 自由基聚合法 亲水性
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Ultrasonic-assisted Synthesis of Fe Nanoparticles in the Presence of Poly(N-vinyl-2-pyrrolidone) 被引量:8
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作者 Xu, Ying Zhang, Xiaoyan +1 位作者 Hsing, Yiming Fang, Yuzhi 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第9期1829-1836,共8页
Zero-valent iron particles were prepared by wet reduction chemistry assisted with ultrasonic treatment. Such prepared particles have uniform size, exhibit crystalline structure and show strong pararnagnetic property. ... Zero-valent iron particles were prepared by wet reduction chemistry assisted with ultrasonic treatment. Such prepared particles have uniform size, exhibit crystalline structure and show strong pararnagnetic property. Their surface modification by coating poly(N-vinyl-2-pyrrolidone) (PVP) was investigated. The resulting Fe(0)-PVP particles were monodispersed and possessed enhancing magnetization saturation. Those synthesis conditions to control the particle size and distribution were exploited. 展开更多
关键词 nanoparticles magnetic properties ultrasonic-assisted wet reduction poly(n-vinyl-2-pyrrolidone)
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磷酸掺杂磺化聚(亚芳基醚)-聚(N-乙烯基咪唑)膜电化学性能研究
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作者 史晋宜 魏庆玲 《化工生产与技术》 CAS 2023年第4期11-14,I0003,共5页
使用磺化聚芳基醚(SDF-F)作为酸性聚合物、聚(N-乙烯基咪唑)(PVIm)作为碱性聚合物,合成了用于高温工作的磷酸掺杂磺化聚(亚芳基醚)-聚(N-乙烯基咪唑)(SDF-F/PVIm)质子交换膜,进行了热损失、电导率、阻抗光谱和单电池性能测试。结果表明,... 使用磺化聚芳基醚(SDF-F)作为酸性聚合物、聚(N-乙烯基咪唑)(PVIm)作为碱性聚合物,合成了用于高温工作的磷酸掺杂磺化聚(亚芳基醚)-聚(N-乙烯基咪唑)(SDF-F/PVIm)质子交换膜,进行了热损失、电导率、阻抗光谱和单电池性能测试。结果表明,SDF-F/PVIm膜热稳定性良好。在无水条件下,交联膜在150~200℃具有很高的质子电导率,且电导率随着温度的升高而增加。在不同的温度下单电池的性能表现优异,在190℃时,可以获得528 mW/cm2最大功率密度,且无需外部加湿。合成的SDF-F/PVIm有望成为高温PEMFCs的新型聚合物电解质。 展开更多
关键词 磺化聚(亚芳基醚)-聚(n-乙烯基咪唑)质子交换膜 磷酸掺杂 电化学 性能
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NOVEL AMPHIPHILIC FLUORESCENT GRAFT COPOLYMER: SYNTHESIS, CHARACTERIZATION AND ENCAPSULATION OF A HYDROPHOBIC AGENT 被引量:2
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作者 Zhao-qiang Wu Shu Yang Wen-yan Liao 孟令芝 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第3期315-321,共7页
Novel amphiphilic fluorescent graft copolymer (PVP-PyAHy) was successfully synthesized by the free radical copolymerization of hydrophobic monomer N-(1-pyrenebutyryl)-N'-acryloyl hydrazide (PyAHy) with hydrophi... Novel amphiphilic fluorescent graft copolymer (PVP-PyAHy) was successfully synthesized by the free radical copolymerization of hydrophobic monomer N-(1-pyrenebutyryl)-N'-acryloyl hydrazide (PyAHy) with hydrophilic precursor polymers of vinyl-functionalized poly(N-vinylpyrrolidone) (PVP) in DMF. The copolymer is amphiphilic and has intrinsic fluorescence. FT-IR, ^1H-NMR, TEM, gel permeation chromatography-multi-angle laser light scattering, UV-Vis spectroscopy and fluorescence spectroscopy were used to characterize this copolymer. The TEM observation shows that the copolymer PVP-PyAHy forms micelles in aqueous solution. Results of fluorometric measurements illustrate that the critical micelle concentration (CMC) value of PVP-PyAHy in aqueous solution is about 0.90 mg/mL. To examine the encapsulation ability of the copolymer in aqueous media, methyl yellow was employed as a model hydrophobic agent. The loading level of the polymer to methyl yellow is 8.8 mg/g. The cytotoxicity assays for Madin Darby Canine Kidney (MDCK) cells shows good biocompatibility of PVP-PyAHy in vitro. These results suggest the potential of this copolymer PVP-PyAHy as drugs delivery carrier and fluorescent tracer. 展开更多
关键词 Amphiphilic copolymer FLUORESCEnCE poly(n-vinylpyrrolidone).
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Kinetic hydrate inhibitor performance of new copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s with TBAB 被引量:8
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作者 Jun Hu Sijia Li +3 位作者 Yanhong Wang Xuemei Lang Qingping Li Shuanshi Fan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第2期126-131,共6页
In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the c... In oil and gas field, the application of kinetic hydrate inhibitors (KHIs) independently has remained problematic in high subcooling and high water-cut situation. One feasible method to resolve this problem is the combined use of KHIs and some synergists, which would enhance KHIs’ inhibitory effect on both hydrate nucleation and hydrate crystal growth. In this study, a novel kind of KHI copolymer poly(N-vinyl-2-pyrrolidone-co-2-vinyl pyridine)s (HGs) is used in conjunction with TBAB to show its high performance on hydrate inhibition. The performance of HGs with different monomer ratios in structure II tetrahydrofuran (THF) hydrate is investigated using kinetic hydrate inhibitor evaluation apparatus by step-cooling method and isothermal cooling method. With the combined gas hydrate inhibitor at the concentration of 1.0 wt%, the induction time of 19 wt% THF solution could be prolonged to 8.5 h at a high subcooling of 6℃. Finally, the mechanism of HGs inhibiting the formation of gas hydrate is proposed. 展开更多
关键词 clathrate hydrate kinetic hydrate inhibitors combined hydrate inhibitors poly(n-vinyl-2-pyrrolidone-co-2-vinyl pyridine)
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Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide) synthesized by ATRP 被引量:2
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作者 Xin De Tang Xiao Chao Liang Nian Feng Han 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1353-1356,共4页
Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM)2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macr... Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM)2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macroinitiator was prepared by esterification of 2,2-dichloroacetyl chloride with poly(ethylene glycol) monomethyl ether (PEG). The copolymers were obtained via the ATRP ofN-isopropylacrylamide (NIPAM) at 30℃ with CuCl/Me6TREN as a catalyst system and DMF/H2O (v/v = 3:1) mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography (GPC) and ^1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions (PDI 〈 1.15). Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry (DSC). As a result, the phase transition temperature of PEG45-b-(PNIPAM55)2 is higher than that of PNIPAM, however, the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular composition and architecture on the phase transition. 展开更多
关键词 Y-shaped Block copolymer poly(ethylene glycol) poly(n-isopropylacrylamide) Atom transfer radical polymerization (ATRP)
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Reversible Aggregation Kinetics of Poly(N-isopropylacrylamide-co-N-vinylpyrrolidone) in Aqueous Solutions Revealed by Elastic Light Scattering Spectroscopy 被引量:1
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作者 夏远军 HUANG Yunwei +3 位作者 易国斌 ZU Xihong YIN Qingshui CHEN Xudong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2013年第4期766-772,共7页
Poly(N-isopropylacrylamide-co-N-vinylpyrrolidone) [P(NIPAM-co-NVP)] copolymers with different content of N-vinylpyrrolidone (NVP) were synthesized, and reversible aggregation kinetics of the copolymers in aqueou... Poly(N-isopropylacrylamide-co-N-vinylpyrrolidone) [P(NIPAM-co-NVP)] copolymers with different content of N-vinylpyrrolidone (NVP) were synthesized, and reversible aggregation kinetics of the copolymers in aqueous solutions was investigated with elastic light scattering (ELS) spectra. The results indicated that the apparent activation energy of aggregation process during heating and dissociation process during cooling increased with the NVP content increasing. The phase transition temperature also increased as the content of NVP increased, suggesting that the hydrophilic nature of NVP strongly affected the phase behavior of the copolymer solutions. The higher the content of NVP, the higher the temperature required to break the balance between the hydrophilic and hydrophobie interaction. Besides, during heating and cooling process, the phase transition hysteresis of P(NIPAM-co-NVP) chains decreased when the hydrophilic comonomer increased. 展开更多
关键词 poly(n-isopropylacrylamide-co-n-vinylpyrrolidone) kinetics aggregation hydrophilicity elastic light scattering spectra
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Synthesis of Poly(N-vinylpyrrolidone) Nanofibers Containing Gold Nanoparticles via Electrospinning Technique 被引量:1
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作者 DU Jian-shi YANG Qing-biao +3 位作者 BAI Jie WANG Shu-gang ZHANG Chao-qun LI Yao-xian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期538-540,共3页
Poly(N-vinylpyrrolidone)(PVP)nanofibers containing gold nanoparticles were prepared by electrospinning method.This simple route was used to prepare composites on a large scale,and the syntheses are simple.The opti... Poly(N-vinylpyrrolidone)(PVP)nanofibers containing gold nanoparticles were prepared by electrospinning method.This simple route was used to prepare composites on a large scale,and the syntheses are simple.The optical property of gold nanoparticles in PVP aqueous solution was investigated by UV-Visible absorption spectra.The morphology of the fibers and the distribution of particles were characterized by transmission electron microscopy.The structure of the composite was characterized by Fourier transform infrared spectroscopy. 展开更多
关键词 Composite nanofiber ELECTROSPInnInG poly(n-vinylpyrrolidone) Gold nanoparticle
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Nano-hydroxyapatite formation via co-precipitation with chitosan-g-poly(N-isopropylacrylamide) in coil and globule states for tissue engineering application 被引量:1
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作者 Yang YU Hong ZHANG +2 位作者 Hong SUN Dandan XING Fanglian YAO 《Frontiers of Chemical Science and Engineering》 SCIE EI CAS CSCD 2013年第4期388-400,共13页
With the excellent biocompatibility and osteo- conductivity, nano-hydroxyapatite (nHA) has shown significant prospect in the biomedical applications. Con- trolling the size, crystallinity and surface properties of n... With the excellent biocompatibility and osteo- conductivity, nano-hydroxyapatite (nHA) has shown significant prospect in the biomedical applications. Con- trolling the size, crystallinity and surface properties of nHA crystals is a critical challenge in the design of HA based biomaterials. With the graft copolymer of chitosan and poly(N-isopropylacrylamide) in coil and globule states as a template respectively, a novel composite from chitosan-g-poly(N-isopropylacrylamide) and nano-hydro- xyapatite (CS-g-PNIPAM/nHA) was prepared via co- precipitation. Zeta potential analysis, thermogravimetric analysis and X-ray diffraction were used to identify the formation mechanism of the CS-g-PNIPAM/nHA compo- site and its morphology was observed by transmission electron microscopy. The results suggested that the physical aggregation states of the template polymer could induce or control the size, crystallinity and morphology of HA crystals in the CS-g-PNIPAM/nHA composite. The CS-g-PNIPAM/nHA composite was then introduced to chitosan-gelatin (CS-Gel) polyelectronic complex and the cytocompatibility of the resulting CS- Gel/composite hybrid film was evaluated. This hybrid film was proved to be favorable for the proliferation of MC 3T3-E1 cells. Therefore, the CS-g-PNIPAM/nHA compo- site is a potential biomaterial in bone tissue engineering. 展开更多
关键词 chitosan poly(n-isopropylacrylamide) hydroxyapatite COIL GLOBULE bone tissue engineering
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Synthesis and Drug Release Properties of Thermosensitive Poly(N-vinylacetamide-co-vinylacetate) Hydrogels 被引量:1
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作者 YANG Li-he CHU Hong CHEN Ming-qing HU Na ZHAO Yi-fan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期334-338,共5页
Thermosensitive poly[N-vinylacetamide-co-vinylacetate][P(NVA-co-VAc)] hydrogels were prepared via free radical copolymerization from hydrophilic NVA and hydrophobic VAc in the presence of butylenes-bis (N-vinylacet... Thermosensitive poly[N-vinylacetamide-co-vinylacetate][P(NVA-co-VAc)] hydrogels were prepared via free radical copolymerization from hydrophilic NVA and hydrophobic VAc in the presence of butylenes-bis (N-vinylacetamide)(Bis-NVA) as crosslinker. Scanning electron microscopy(SEM) images reveal that the as-prepared hydrogels were of three-dimensional network with irregular cave structure. The prepared hydrogels with more NVA in the feed swelled faster and the swelling ratio of the hydrogels gradually decreased with temperature increasing from 10 °C to 60 °C. The dynamic swelling studies indicate that the swelling process of the hydrogels was controlled by diffusion of water molecules considered as Fickian-controlled case. The adsorption amount of model drug, sodium salicylate(SS) was higher in the hydrogels containing more NVA units, whose corresponding release could reach equilibrium in about 6 h. 展开更多
关键词 poly(n-vinylacetamide-co-vinylacetate) Therrnosensitive hydrogel Drug release
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Preparation of poly(N-isopropylacrylamide) brush grafted silica particles via surface-initiated atom transfer radical polymerization used for aqueous chromatography 被引量:2
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作者 Zong-Jian LIU Yan-Li LIANG +4 位作者 Fang-Fang GENG Fang LV Rong-Ji DAI Yu-Kui ZHANG Yu-Lin DENG 《Frontiers of Materials Science》 SCIE CSCD 2012年第1期60-68,共9页
Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) brushes were densely grafted onto silica surface via surface-initiated atom transfer radical polymeriza- tion (SI-ATRP). The grafting reaction started from ... Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) brushes were densely grafted onto silica surface via surface-initiated atom transfer radical polymeriza- tion (SI-ATRP). The grafting reaction started from the surfaces of 2-bromoisobutyrate- functionalized silica particles in 2-propanol aqueous solution at ambient temperature using CuCIICuCI21N, N,N',N',N”.pentamethyldiethylenetriamine (PMDETA) as the catalytic system. Based on thermogravimetric analysis (TGA) results, the grafting amount and grafting density of PNIPAM chains on the surface of silica were calculated to be 1.29 mg/ m^2 and 0.0215 chains/nm^2, respectively. The gel permeation chromatography (GPC) result showed the relatively narrow molecular weight distribution (MwlMn= 1.21) of the grafted PNIPAAm. The modified silica particles were applied as high-performance liquid chromatography (HPLC) packing materials to successfully separate three aromatic compounds using water as mobile phase by changing column temperature. Temperature- dependent hydrophilic/hydrophobic property alteration of PNIPAAm brushes grafted on silica particles was determined with chromatographic interaction between stationary phase and analytes. Retention time was prolonged and resolution was improved with increasing temperature. Baseline separation with high resolution at relatively low temperatures was observed, demonstrating dense PNIPAAm brushes were grafted on silica surfaces. 展开更多
关键词 poly(n-isopropylacrylamide) (PnIPAAm) atom transfer radical polymeriza-tion (ATRP) temperature-responsive chromatography separation
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基于温敏性N,N-二甲基丙烯酰胺/N-异丙基丙烯酰胺无规共聚物的毛细管无胶电泳筛分介质 被引量:3
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作者 江凤浩 洪瀚 +1 位作者 姜伯玮 苏朝晖 《应用化学》 CAS CSCD 北大核心 2023年第9期1312-1321,共10页
本文合成了N,N-二甲基丙烯酰胺/N-异丙基丙烯酰胺无规共聚物(P(DMA-co-NIPAM))和聚N,N-二甲基丙烯酰胺(PDMA),并将二者共混制备毛细管无胶电泳筛分介质,旨在降低筛分介质粘度的同时增强其对DNA的分离性能。核磁共振氢谱(1H NMR)和傅里... 本文合成了N,N-二甲基丙烯酰胺/N-异丙基丙烯酰胺无规共聚物(P(DMA-co-NIPAM))和聚N,N-二甲基丙烯酰胺(PDMA),并将二者共混制备毛细管无胶电泳筛分介质,旨在降低筛分介质粘度的同时增强其对DNA的分离性能。核磁共振氢谱(1H NMR)和傅里叶变换红外光谱(FT-IR)证明了2种聚合物的成功合成。表征了P(DMA-co-NIPAM)/PDMA共混物溶液的流体力学直径(Dh)、低剪切粘度和吸光度,结果表明,P(DMAco-NIPAM)聚合物具有温敏性,低临界溶解温度(LCST)为60~80℃。DNA筛分结果显示,PDMA中添加了10%P(DMA-co-NIPAM)的复合筛分介质性能最好,相比PDMA粘度降低19%以上,对大DNA片段的分辨率和理论塔板数均明显提高,分离时间缩短4%,显示了优良的分离性能。 展开更多
关键词 毛细管电泳 毛细管无胶电泳筛分介质 DnA分离 温敏性聚合物 n n-二甲基丙烯酰胺
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Microwave-assisted Preparation of Temperature Sensitive Poly(N-isopropylacrylamide) Hydrogel with Improved Responsive Properties
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作者 Shao Hua SHI Li Jian LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第3期361-364,共4页
Poly(N-isopropylacrylamide)-based hydrogel was prepared under microwave irradiation The hydrogel thus prepared, comparing with that prepared by thermal heating method, exhibits faster swelling and shrinking kinetics... Poly(N-isopropylacrylamide)-based hydrogel was prepared under microwave irradiation The hydrogel thus prepared, comparing with that prepared by thermal heating method, exhibits faster swelling and shrinking kinetics. The improved responsive properties are due to the more heterogeneous and porous networks formed under microwave irradiation. 展开更多
关键词 MICROWAVE poly(n-isopropylacrylamide) HYDROGEL fast response.
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