检索结果-南通市图书馆

Slightly Cross-Linked Polyrotaxanes Made by Linking α-Cyclodextrins Entrapped in Polyrotaxanes Using hexamethylene diisocyanate

引用

Chinese Journal of Chemistry 2012年第10期30卷 2453-2460页

作者：李硕王锦姜岚叶霖张爱英冯增国 School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

In this study polyrotaxane （PR）-based triblock copolymers were first synthesized via the atom transfer radical polymerization （ATRP） of N-isopropylacrylamide initiated with the self-assembly of a distal 2-bromoisobutyryl end-capped Pluronie 17R4 with a varying amount of a-cyclodextrins （a-CDs） in the presence of CuCI/PMDETA at 25 ℃ in aqueous solution. The a-CDs entrapped on the copolymer chain were then linked with hexamethylene diisocyanate to give rise to novel slightly cross-linked polyrotaxanes （SCPRs） in DMF at 45 ℃. The structures of the PR-based triblock copolymers and SCPRs were characterized by 1H NMR, 13C CP/MAS, GPC and TGA analy- ses. The number-average molecular weight of the resulting SCPRs was nearly three and five times of their precursor after linking with a low polydispersity index range of 1.08--1.28. The thermo-responsive transition of both PR-based supramolecular polymers in aqueous solution was demonstrated by turbidity measurements and the self-aggregated morphologies were also evidenced by TEM observations.

关键词： α-cyclodextrin polyrotaxane ATRP poly(N-isopropylacrylamide) hexamethylene diisocyanate

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Curing for Modified Vinyl Ester Resin by hexamethylene diisocyanate and Its Influence on Performances

引用

Journal of Wuhan University of Technology(Materials Science) 2022年第2期37卷 300-304页

作者： KUANG Yali FENG Jing YU Miao CUI Kaimin HAN Wei ZHANG Jihong Materials and Structure Department Changjiang River Scientific Research InstituteWuhan 430010China State Key Laboratory of Silicate Materials for Architecture Wuhan University of TechnologyWuhan 430070China

The commercial vinyl ester resins(VER)was modified by diphenylmethane diisocyanate(MDI)to enhance its toughness,which is called *** diisocyanate(HDI),a common curing agent for polyurethane(PU),was found to be a reactive agent for MVER and can contribute to the toughness of *** on present experiment results,the crosslinking mechanism of MVER and HDI system is very similar to that of *** FTIR result shows the-NCO of HDI can react with the-OH of *** microstructure of material prepared by MVER and HDI was characterized by NMR,and it was revealed that the unique microstructure leads to the good *** different content of HDI has an influence on the microstructure,and the microstructure gradually reduces the toughness and mechanical performances of the MVER cured with increasing concentration of reactive curing agent(HDI).This feature is consistent with a maximum in toughness as a function of the additive(HDI)content,followed by a rapid deterioration in toughness at higher *** toughness exhibits the maximum at such an HDI concentration(20wt%).Therefore,the special curing agent(HDI)and reactive mode is very important to the microstructure and mechanical properties of ***,there should be other reactions which contribute to the curing and microstructure of the material,which needs the further research.

关键词： modified vinyl ester hexamethylene diisocyanate mechanical properties toughness

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A ONE-STEP SURFACE MODIFICATION PROCEDURE TO PEG-GRAFTED NANO-TITANIA

引用

Chinese Journal of Polymer Science 2007年第3期25卷 291-296页

作者：郭朝霞 Institute of Polymer Science and Engineering Department of Chemical EngineeringSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

PEG （Polyethylene Glycol）-grafted nano-titania has been obtained in a one-step procedure using hexamethylene diisocyanate as the coupling agent and dibutyltin dilaurate as the catalyst in toluene at 80℃ and characterized qualitatively by FTIR and quantitatively by elemental analysis and thermogravimetric analysis. A comparison of nano-titania with two other commonly used inorganic nanoparticles, nano-silica and nano-alumina, is made, revealing that reactivity order is nano- silica 〉 nano-alumina 〉 nano-titania in view of PEG grafting. Possible mechanism of PEG grafting is also discussed.

关键词： Nano-titania PEG hexamethylene diisocyanate Surface modification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Synthesis and Characterization of HDI/MDI-Polycarbonate Urethanes

引用

Transactions of Tianjin University 2010年第5期16卷 317-321页

作者：郭锦棠殷俊威冯亚凯 School of Chemical Engineering and Technology Tianjin University

A novel polycarbonate urethane was synthesized by the two-stage solution process of diisocyanates with polycarbonate diols(PCDL),in which PCDL,1,4-butanediol(BD) and mixture of 4,4 -methylenediphenyl diisocy-anate and hexamethylene diisocyanate(HDI) were soft segment,chain extender and rigid segment,*** structures were characterized by using FTIR and *** thermoanalysis and mechanical properties of products were measured by means of DSC,TG and other *** result shows that an import...

关键词： polycarbonate urethane hexamethylene diisocyanate diphenyl-methane-diisocyanate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：