共轭三组分互穿聚合物网络的力学性能和形态：聚氨 …

基于共轭三组分互穿聚合物网络和界面共轭互穿这两个新概念,通过互穿聚合物网络技术成功地制备了聚氧化丙烯二元醇聚氨酯／聚（甲基丙烯酸甲酯－共－三烯丙基异氰脲酸酯）／废胶粉ＣＴＣ－ＩＰＮ（ＰＵ／Ｐ（ＭＭＡ－ｃｏ－ＴＡＩＣ）／ＳＲＰ－ＣＴＣ－ＩＰＮ）,研究了这种材料以及ＰＵ／ＳＲＰ共混笺的力学性能。结果表明,ＰＵ／Ｐ（ＭＭＡ－ｃｏ－ＴＡＩＣ）／ＳＲＰ－ＣＴＣ－ＩＰＮ由于含公共网络Ｐ（ＭＭＡ－ｃｏ－ＴＡＩＣ     

聚氨酯／聚丙烯酸酯互穿聚合物网络的动态热机械特性

用动态机械法（ＤＭＡ）研究了聚氨酯／聚丙烯酸酯互穿事物网络（ＰＵ／ＰＥＡＩＰＮ）的动态机械特性,并分别与单纯的聚氨酯（ＰＵ）和聚丙烯酸乙酯（ＰＥＡ）的动态热机械性能进行对比。结果表明：在玻璃化温度以下,ＰＵ／ＰＥＡＩＰＮ的ＤＭＡ曲线振幅小于单纯的ＰＵ和ＰＥＡ;当完全进入高弹态后,ＩＰＮ的ＤＭＡ曲线振幅大于单纯的ＰＵ和ＰＥＡ。ＰＵ／ＰＥＡＩＰＮ的玻璃化转变温度别比ＰＵ和ＰＥＡ提高１６．２和３０．１度     

互穿聚合物网络的高分辨裂解色谱—质谱研究

本文用高分辨裂解色谱－质谱法（ＨＲＰｙＧＣ—ＭＳ）研究了聚醚型聚氨酯／聚（苯乙烯－共－二乙烯苯）互穿聚合物网络［ＰＵ／Ｐ—ｃｏ—ＤＶＢ）—ＩＰＮ］热分解过程的特征、裂解产物的组成和分布；ＩＰＮ与其组分聚合物的裂解谱图比较表明，ＰＵ／Ｐ（Ｓｔ—ｃｏ—ＤＶＢ）是一种两网络间不存在化学结合的典型的互穿聚合物网络。由热失重曲线发现ＩＰＮ材料有两个热分解阶段；从裂解产物的温度依赖性和分步裂解色谱分析并结合动态热重法结果讨论了其热分解机理。     

PVC／PBA和PS／PBA两种LIPN的性能与相容性

通过对ＰＶＣ／ＰＢＡ（聚氯乙烯／聚丙烯酸丁酯）和ＰＳ／ＰＢＡ（聚苯乙烯／聚丙烯酸丁酯）两种ＬＩＰＮ的玻璃化转变温度Ｔｇ和动态力学等性能的测定，比较了它们的相容性和阻尼性能。实验结果表明ＰＶＣ／ＰＢＡＬＩＰＮ的相容性和阻尼性能较ＰＳ／ＰＢＡＬＩＰＮ更好     

聚氨酯／聚丙烯酸酯类胶乳互穿聚合物网络的研制—乳胶粒径与原料配比的关系

本文讨论了聚氨酯（ＰＵ）／聚丙烯酸酯（ＰＡＡ）类胶乳互穿聚合物网络（ＬＩＰＮ）粒径与原料配比的关系。试验结果表明影响ＰＵ／ＰＡＡＬＩＰＮ的粒径的关键因素是亲水基团（ＣＯＯＨ）的含量以及成盐率     

MULTIPARAMETERINVERSIONOFELASTICWAVEWITHSINGLEIMPULSESOURCE

ＭＵＬＴＩＰＡＲＡＭＥＴＥＲＩＮＶＥＲＳＩＯＮＯＦＥＬＡＳＴＩＣＷＡＶＥＷＩＴＨＳＩＮＧＬＥＩＭＰＵＬＳＥＳＯＵＲＣＥＣｈｅｎｇＪｉａｎｃｈｕｎＴａｏＸｉｕｐｉｎｇＷｅｉＹｏｎｇＺｈａｎｇＳｈｕｙｉ（ＩｎｓｔｉｔｕｔｅｏｆＡｃｏｕｓｔｉｃｓａｎｄＬ...     

UNIX工作站对远程ORACLE FOR NETWARE数据库的访问

研究了ＵＮＩＸ与ＴＣＰ／ＩＰ系统以及ＩＰ地址命名规则、ＮＯＶＥＬＬ的开放式互联接口，提出ＵＮＩＸ工作站同时访问ＵＮＩＸ宿主机和ＯＲＡＣＬＥＦＯＲＮＥＴＷＡＲＥ的方案及有关实现技术，可实现跨平台数据库的互访．     

矿用斜巷绞车语言声光信号装置

矿用斜巷绞车语言声光信号装置①温学锋（中国煤炭科学总院太原分院，太原０３０００１）ＭＩＮＥＬＡＮＧＵＡＧＥ—ＬＩＧＨＴ—ＳＯＵＮＤＳＩＧＮＡＬＬＩＮＧＤＥＶＩＣＥＦＯＲＳＫＩＰＷＩＮＣＨＷｅｎＸｕｅｆｅｎｇ（ＴａｉｙｕａｎＢｒａｎｃｈｏｆＣｅｎｔｒａ...     

UNIX与NOVELL互联的解决方法

简述ＴＣＰ／ＩＰ的原理，应用及用ＴＣＰ／ＩＰ解决ＵＮＩＸ和ＮＯＶＥＬＬ的互联。     

LIPN聚氨酯/聚丙烯酸酯引发体系的研究

探讨了各种引发体系对ＬＩＰＮ聚氨酯（ＰＵ）／聚丙烯酸酯（ＰＡ）合成过程的稳定性、粒子形态及单体转化率的影响。实验表明采用油溶性引发剂ＡＩＢＮ可得到粒子均一,稳定性好且单体残留量很少的乳液;其粒子形态为“翻转”型核壳结构     

聚氨酯/苯并(口恶)嗪互穿聚合物网络的合成及表征

采用二步法 ,以部分交联的聚氨酯 (PU)为聚合物 ,以双酚 A型苯并嗪 (BA)为聚合物 合成了聚氨酯 /苯并嗪互穿聚合物网络 (PU/BA IPN) ,对产物的性能进行了研究 ,同时应用升温红外对 PU/BA IPN的聚合进行动态跟踪 .结果表明 ,材料的热力学性能受体系结构形态的影响较大 .而形态主要由聚合物 (即 PU)的交联密度控制 ,体系的组成对形态影响呈非线性 .体系中存在的活性官能团——氨基团对苯并嗪的开环聚合有催化作用 .     

共轭三组分互穿聚合物网络的力学性能和形态——聚氨酯/聚甲基丙烯酸甲酯/废胶粉体系

基于共轭三组分互穿聚合物网络 (CTC_IPN)和界面共轭互穿这两个新概念 ,通过互穿聚合物网络技术成功地制备了聚氧化丙烯二元醇聚氨酯 /聚 (甲基丙烯酸甲酯 共 三烯丙基异氰脲酸酯 ) /废胶粉CTC_IPN(PU/P(MMA_co_TAIC) /SRP_CTC_IPN ) ,研究了这种材料以及PU/SRP共混物的力学性能 .结果表明 ,PU /P(MMA_co_TAIC) /SRP_CTC_IPN由于含公共网络P(MMA_co_TAIC) ,其性能明显优于PU/SRP共混物 .用扫描电子显微镜 (SEM )和透射电子显微镜(TEM )研究了PU/P(MMA_co_TAIC) /SRP_CTC_IPN和PU/SRP共混物的断面形貌 ,结果表明 ,两者具有完全不同的断裂机理 .TEM结果表明 ,P(MMA_co_TAIC)网络能分别与PU及SRP网络互穿 ,从而改善了两者之间的界面结合     

Gas Permeability and Free Volume Hole Properties of Interpenetrating Polymer Network Studied by Positrons

A series of polyurethane/epoxy resin interpenetrating polymer networks （PU/ER IPN） were studied by positron annihilation lifetime spectroscopy （PALS）. The effects of epoxy resin type and content on the free volume properties in IPN were investigated. We found that in PU/ER IPN, the free volume hole size and fractional free volume showed a negative deviation due to closer segmental chain packing through some chemical bonding between PU and epoxy resin. Direct relationship between the gas permeability and the free volume has been established based on the free volume theory. Experimental results revealed that the free volume plays an important role in determining the gas diffusion and permeability.     

The reaction cycle of isopenicillin N synthase observed by X-ray diffraction.

Isopenicillin N synthase (IPNS), a non-haem iron-dependent oxidase, catalyses the biosynthesis of isopenicillin N (IPN), the precursor of all penicillins and cephalosporins. The key steps in this reaction are the two iron-dioxygen-mediated ring closures of the tripeptide delta-(L-alpha-aminoadipoyl)-L-cysteinyl-D-valine (ACV). It has been proposed that the four-membered beta-lactam ring forms initially, associated with a highly oxidized iron(iv)-oxo (ferryl) moiety, which subsequently mediates closure of the five-membered thiazolidine ring. Here we describe observation of the IPNS reaction in crystals by X-ray crystallography. IPNS Fe2+ substrate crystals were grown anaerobically, exposed to high pressures of oxygen to promote reaction and frozen, and their structures were elucidated by X-ray diffraction. Using the natural substrate ACV, this resulted in the IPNS x Fe2+ x IPN product complex. With the substrate analogue, delta-(L-alpha-aminoadipoyl)-L-cysteinyl-L-S-methylcysteine (ACmC) in the crystal, the reaction cycle was interrupted at the monocyclic stage. These mono- and bicyclic structures support our hypothesis of a two-stage reaction sequence leading to penicillin. Furthermore, the formation of a monocyclic sulphoxide product from ACmC is most simply explained by the interception of a high-valency iron-oxo species.     

甲基丙烯酸甲酯改性聚醚聚氨酯的结构形态与力学性能

采用同步法合成了聚氨酯(PU)/聚甲基丙烯酸甲酯(PMMA)的线型共混物、嵌段共聚物和互穿高聚物(IPN)。凭藉力学性能测试、电镜观察和动态力学谱分析,研究了光固化、热固化、化学组成、物理结构等因素对体系力学性能、结构形态和粘弹行为的影响。结果表明:PU/PMMA是呈两相结构的部分相容体系,其中线型共混物伸长率最大,IPN强度最高,而嵌段共聚物的力学性能较差。此外,嵌段共聚物和IPN光固化体系形成的相畴结构均一,其抗张强度和伸长率明显高于热固化体系。聚合物的力学性能除了受化学结构影响以外,还与化学组成有关,随体系中PMMA含量和PU中硬链段含量增加,聚合物抗张强度升高,伸长率下降。     

Structure and Properties of Polytetrafluorethylene and Polyurethane Layered Membrane for Protective Clothing

IntroductionProtective clothing articles used for wear in wetconditions ; in outdoor activities ; in handling hazardouschemicals , in preventing contamination, in avoidinginfection, should in each instance protect the wearer bypreventing leakage of water or other fluids andmicroorganisms into the article while keeping the wearercomfortable by allowing perspiration to evaporate from thewearer to the outside of the article .In additionto the above ,the amount of stretch and its recovery and the …     

TDI-PTMG型PU/PMMA/OMMT纳米复合材料的结构及性能研究

将插层纳米复合技术与同步互穿聚合物网络(IPN)技术相结合,制备了聚氨酯(PU)/聚甲基丙烯酸甲酯(PMMA)/有机蒙脱土(OMMT)纳米复合材料.用透射电子显微镜(TEM)和力学性能测试研究了该复合材料和相应的PU/PMMA-IPN和PU材料的结构和力学性能.结果表明.PU/PMMA/OMMT纳米复合材料形成了插层/剥离型结构,其力学性能最优.对材料的制备工艺进行了研究,获得优化制备条件是:PU/PMMA质量比为60/40;OMMT,BPO,EGDMA添加量分别为单体MMA质量的5%,0.8%,2.0%,MOCA系数为0.9.