明胶反相乳化接枝改性胶粘剂的制备与性能研究

在断裂或开裂古墨文物的修复中,必须使用与古墨本体相容性好、亲和力强的溶剂型胶粘剂。以古墨中的胶质材料明胶（GEL）为主,以丙烯酸丁酯（BA）、丙烯腈（AN）为辅,在两种非离子乳化剂复配的条件下,采用反相乳液接枝共聚法合成了一种专用于修复受损古墨的接枝改性明胶胶粘剂。采用红外光谱（FT-IR）技术对其结构进行了表征,试验探讨了各种因素对乳液稳定性、接枝率和接枝效率的影响。研究结果表明：当明胶的预处理时间为2h、搅拌速率为300r/min、反应温度为50℃、反应时间为2.5h和w（复合乳化剂）=10%（相对于油相而言）时,制取的接枝改性明胶胶粘剂能够满足古墨文物粘接修复的使用要求。     

大豆蛋白乳液胶粘剂的研制

由于以石化原料合成的胶粘剂在生产和使用过程中会对环境带来不良影响,近年来采用可再生资源,如大豆蛋白合成环保型胶粘剂已成为发展趋势。以尿素和亚硫酸钠改性大豆分离蛋白(SPI),并与醋酸乙烯酯(VAc)等复合单体在过硫酸铵(APS)引发下进行接枝共聚反应,合成了性能较好的VAc/SPI接枝共聚乳液胶粘剂,降低了原料成本。通过正交实验研究了不同的反应条件对该乳液胶粘剂性能的影响,优化的反应条件是采用半连续乳液聚合工艺,以改性SPI自身作为保护胶体,改性剂尿素的浓度为3mol/L,复合单体与SPI的质量比为2.0:1,反应温度为68℃,共聚反应时间为4～5h。由此制得的乳液胶粘剂具有良好的综合性能。     

一种可修复型木皮贴面胶粘剂及其合成方法

正本发明公开了一种可修复型木皮贴面胶粘剂及其合成方法,其主要成分包括自来水、聚乙烯醇、工业明胶、乳化剂、引发剂、甲基丙烯酸、N-羟乙基丙烯酰胺、醋酸乙烯酯、双(N-乙撑脲基乙基)马来酸酯、拜耳水性聚氨酯树酯、增塑剂、缓冲剂、消泡剂和防腐剂。本发明在制备时首先利用聚乙烯醇和工业明胶为保护胶体,合成自交联聚醋酸乙烯酯共聚改性乳液,然后在共聚乳液中加入一种热活化型聚氨酯胶粘剂DISPERCOLLU54,最终制备出一种性能     

有机硅接枝改性纯丙复合乳液的合成及性能研究

采用两步法聚合工艺制备了含双键有机硅氧烷官能团单体与D4进行乳液缩聚后再与(甲基)丙烯酸酯类单体进行自由基接枝共聚的改性纯丙复合乳液，考查了聚合过程的乳化剂体系、反应温度和时间对单体转化率的关系及对乳液稳定性的影响。得到最佳工艺条件为：第一步采用阴离子型乳化剂DSBA／与非离子乳化剂聚氧乙烯壬基苯基醚系列并用，使含双键有机硅氧烷官能团单体先与D4进行乳液缩聚，反应温度为85～90℃，平衡反应时间3～4小时，中和后得到有机硅预聚体乳液。第二步采用阴离子型乳化剂MS-1与非离子乳化剂NP-40并用的复合乳化剂及APS引发剂进行引发，将第一步反应生成的乳液滴入此段反应过程进行接枝共聚，反应温度为75～80℃，反应时间5～6小时，最终得到有机硅接枝改性纯丙复合乳液。在固定复合乳液中乳化剂总含量≤2．5％的前提下，复合乳化剂的HLB值在12．0左右为宜，确定了各单体的比例为m(BA)：m(MMA)：m(硅单体)为47：44：9，测试结果表明改性复合共聚乳液粘度适中，为热力学稳定体系，其机械稳定性、化学稳定性均达到要求，用改性乳液配制的外墙乳胶涂料的性能较普通市售纯丙乳液具有较大程度的提高。     

用废旧聚苯乙烯泡沫塑料制备改性的乳液型PS胶粘剂

以废旧聚苯乙烯（ＰＳ）泡沫塑料为主要原料，经ＭＡ接枝改性、ＰＦ共混改性和乳化三步工艺研制出改性的ＰＳ乳液型胶粘剂。叙述了该胶的生产工艺流程，讨论了溶剂、改性剂及乳化剂对其性能的影响，确定了反应原料的配比。     

有机硅改性VAc/BA/AA共聚乳液胶粘剂的研究

介绍了有机硅改性 VAc/BA/AA共聚乳液胶粘剂的合成工艺 ,讨论了预乳化工艺、乳化剂体系、PVC及改性共聚单体对粘接强度、耐水性等乳液性能的影响 ;结果表明 ,通过采用预乳化工艺、适宜的乳化剂体系和 PVA,引入有机硅、BA、AA等单体对 PVAc乳液进行共聚改性 ,可以合成综合性能优异的乳液胶粘剂     

胶合板用改性玉米淀粉胶粘剂的研制

采用普通玉米淀粉,通过丙烯酰胺接枝改性,同时采用封闭型异氰酸酯和三羟甲基苯酚(TMP)作交联剂,合成了一种改性玉米淀粉胶粘剂.对各种影响因素进行系统比较研究,选用乙烯.醋酸乙烯共聚乳液(VAE)作分散剂,采用亚硫酸氢钠对芳香族异氰酸酯预聚体(PTDI)进行封闭,提高了淀粉胶粘剂的耐水性能和胶接性能.达到Ⅱ类胶合板的使用要求.     

二聚酸改性水性环氧乳液的研制及其性能研究

以二聚酸与双酚A型环氧树脂为主要原料,采用接枝嵌段工艺制得二聚酸改性环氧树脂乳液,并用傅里叶红外光谱仪(FTIR)对其结构进行了表征。考察了乳化温度与乳化剂用量对乳液性能的影响。与传统水性环氧(E-20)乳液涂料相比,二聚酸改性环氧乳液涂料涂层具有较好的柔韧性、耐冲击性,以及优良的耐水性。     

丙烯酸固相接枝制备高稳定性改性聚乙烯蜡微乳液

旨在对低密度聚乙烯蜡进行化学接枝改性,改善其可乳化性能,从而制备高稳定性改性聚乙烯蜡微乳液。首先以丙烯酸作为接枝单体,采用悬浮溶胀接枝法对低密度聚乙烯蜡进行化学接枝改性;然后,通过选取适当的阴离子乳化剂和非离子乳化剂的复配体系,对接枝改性的聚乙烯蜡产物进行乳化。结果表明：采用SDS和Tween80等比例复配,控制乳化温度为90～95℃,乳化剂用量为聚乙烯蜡的10%、乳化时间为30min时,采用相转变乳化法可制得高稳定性的聚乙烯蜡微乳液。采用FTIR对改性聚乙烯蜡进行了结构表征,证明了丙烯酸被成功地接枝到了聚乙烯蜡分子上,并通过DSC分析研究了其熔点和结晶情况的变化：聚乙烯蜡的熔点为102.41℃,丙烯酸接枝改性聚乙烯蜡的熔点为102.85℃;改性聚乙烯蜡与未改性的聚乙烯蜡的比结晶度为77.7%。     

甲基丙烯酸改性环氧树脂乳液性能的研究

采用甲基丙烯酸化学接枝改性环氧树脂成盐法制得自乳化水分散液,不需外加乳化剂,考查了乳液的力学、稀释、冻融和贮存稳定性,测得乳液pH值应用范围7~9,乳液成膜性能好,尤其是优良的粘附力、柔韧性和耐化学品性等,适于用作胶粘剂和涂料等。     

微晶纤维素的氧化及吸附性能

以微晶纤维素为原料,高碘酸钠(NaIO4)作氧化剂制备了氧化纤维素,考察了反应时间、高碘酸钠与微晶纤维素投料比、反应温度和溶液pH等条件对醛基的影响;为了减少醛基的不良反应,用明胶作包覆材料合成了包醛氧化纤维素,测定了氧化纤维素和包醛氧化纤维素的吸附性能。发现反应时间3h、m(高碘酸钠)/m(微晶纤维素)=2、反应温度35℃、pH=2和w(明胶)=1%,可获得较多醛基;吸附力随醛基的增多而提高;用明胶包覆后醛基数量虽然减少,但吸附力明显提高,其中w(明胶)=3%时吸附力最大,达到31 5mg/g,经5～12h达到吸附平衡。     

利用膦鞣革屑制备胶原蛋白类除醛剂

以有机膦鞣革屑为原料,采用碱-酶两步法提取胶原蛋白,单因素实验结果表明:在m(氧化镁)∶m(革屑)=0.06∶1,反应温度70℃,反应时间2.5 h,m(碱性蛋白酶)∶m(革屑)=0.006∶1的条件下,提胶率达88%。采用多媒体显微镜、红外光谱仪以及凝胶渗透色谱仪对最优条件下提取的胶原蛋白进行了结构分析,并与市售的明胶水解产物做了分析对比。结果表明:提取的胶原蛋白与市售的明胶水解产物的谱图基本一致,市售的明胶水解产物的平均相对分子质量为1 346和564,而提取的胶原蛋白的平均相对分子质量较大,为1 928和755,说明提取的物质为胶原多肽和氨基酸的混合物。应用实验结果表明:当胶原多肽溶液的用量为80 mL/m3时,甲醛去除率可达81%。     

胶片杀菌剂应用研究

就几种杀菌剂对感光材料中明胶的防腐防霉作用进行了应用试验研究,通过对试验结果的分析,筛选出在防腐防霉过程中作用明显的杀菌剂及杀菌剂组合。     

Multifunctional,pH‐responsive graft copolymer prepared from deproteinized natural rubber and 4‐vinylpyridine via emulsion polymerization

We investigated the synthesis of a pH‐responsive graft copolymer of natural rubber and 4‐vinylpyridine. The grafting reaction was carried out using deproteinized natural rubber (DPNR) latex, with potassium persulfate as a free radical initiator. The pH responsiveness of the graft copolymer was investigated using water swelling and contact angle measurements, and was compared with that of pure DPNR. The graft copolymer was found to become responsive in solution at a pH of around 4. Indigo carmine adsorption studies identified the Langmuir isotherm, suggesting monolayer coverage. The adsorbed indigo carmine, a model anionic drug, and carbon dots, an emerging nanosized fluorophore, could be released from the graft copolymer by lowering the pH of the solution. The graft copolymer was tested as a heavy metal adsorbent, and demonstrated selectivity to copper(II) ions. The graft copolymer of 4‐vinylpyridine and DPNR developed in this study is therefore a multifunctional, pH‐responsive material with a wide range of potential applications, including sensing and catalysis, as a biomedical material and as an adsorbent. © 2017 Society of Chemical Industry     

Graft copolymerization coating of methacryloyloxyethyl diphenyl phosphate flame retardant onto silk surface

This paper reports an efficient surface modification methodology to increase fire resistance properties of silk fabric performed by radio frequency (RF) plasma-induced graft copolymerization of vinyl phosphate ester as nanometer coating. Methacryloyloxyethyl diphenyl phosphate (MEDP) monomer was prepared and graft-copolymerized onto the surface of silk fabric by argon RF plasma at ambient temperature. Under optimum RF power (30 W), amounts of MEDP and N,N methylenebisacrylamide cross linking agent were varied to obtain optimum graft copolymerization conditions. Untreated and treated silk were characterized by attenuated total reflectance infrared (ATR-IR) spectroscopy to investigate their functional group characteristics. This showed a strong covalent attachment between the surface of silk and flame retardant material as the carbonyl functionality of the MEDP was clearly observed in the spectra. Scanning electron microscopic (SEM) analysis also showed grafted material as nanometer residue on silk surface. Thermogravimetric analysis (TGA) revealed that the decomposition of phosphorus compound which occurs at lower temperature than that of silk itself resulted in the formation of char which covers the surface of the fabrics. This protects the fabric surface from further burning, therefore, higher amounts of remaining materials were observed as char in all cases. Furthermore, the limiting oxygen index (LOI) increased from 25.5 for untreated to 28.0 (ca. 10%) for the MEDP-grafted silk. Higher amounts of char were also observed in the case of MEDP-treated silk. After 5 dry cleaning cycles, the LOI of the treated silk dropped only very slightly. Detailed analysis on structural and thermal properties as well as surface grafting efficiency are presented.     

Ex Vivo and In Vivo Analysis of a Novel Porcine Aortic Patch for Vascular Reconstruction

(1) Background: The aim of the present study was the biocompatibility analysis of a novel xenogeneic vascular graft material (PAP) based on native collagen won from porcine aorta using the subcutaneous implantation model up to 120 days post implantationem. As a control, an already commercially available collagen-based vessel graft (XenoSure^®) based on bovine pericardium was used. Another focus was to analyze the (ultra-) structure and the purification effort. (2) Methods: Established methodologies such as the histological material analysis and the conduct of the subcutaneous implantation model in Wistar rats were applied. Moreover, established methods combining histological, immunohistochemical, and histomorphometrical procedures were applied to analyze the tissue reactions to the vessel graft materials, including the induction of pro- and anti-inflammatory macrophages to test the immune response. (3) Results: The results showed that the PAP implants induced a special cellular infiltration and host tissue integration based on its three different parts based on the different layers of the donor tissue. Thereby, these material parts induced a vascularization pattern that branches to all parts of the graft and altogether a balanced immune tissue reaction in contrast to the control material. (4) Conclusions: PAP implants seemed to be advantageous in many aspects: (i) cellular infiltration and host tissue integration, (ii) vascularization pattern that branches to all parts of the graft, and (iii) balanced immune tissue reaction that can result in less scar tissue and enhanced integrative healing patterns. Moreover, the unique trans-implant vascularization can provide unprecedented anti-infection properties that can avoid material-related bacterial infections.     

疏松型纳米氢氧化镁阻燃聚丙烯

以聚丙烯(PP)为基体,疏松型纳米氢氧化镁(LN-MH)为主阻燃剂,红磷和炭黑为协同阻燃剂,制备了阻燃材料。实验结果表明:包覆剂A8使PP／LN-MH复合材料[(m(PP)／m(LN-MH)为100:40)]力学性能最佳;偶联剂KH550和接枝物又进一步提高了复合材料的力学性能,使PP／LN-MH复合材料和纯PP相当;LN-MH的加入提高了PP的熔融峰温度,降低了结晶度和热失重起始温度,接枝物的加入进一步提高了熔融峰温度,相对增加了结晶度;红磷和炭黑的加入表现出良好的协同作用,在低LN-MH填充量时,加入9 phr红磷或7 phr红磷和5 phr炭黑后阻燃级别达到UL 94 V-0级;通过偶联剂和接枝物进一步改性,能够使复合材料在达到阻燃要求的同时保持良好的力学性能。     

Combination of atom transfer radical polymerization and click chemistry toward cellulose-rosin derived UV-absorbent copolymers

UV absorption coating is an important function material, which can protect the substrates from photoaging. In this work, a class of sustainable UV-absorbent copolymers derived from ethyl cellulose (EC), fatty acid and rosin were prepared by a combination of atom transfer radical polymerization (ATRP) and click chemistry. To fulfill this strategy, the pendant azides were first attached onto the backbone of EC. Then, ATRP was applied to fabricate well-defined poly(lauryl methacrylate) (PLMA) bearing terminal alkynes. Finally, click chemistry between the pendant azides in EC and the alkynes in PLMA as well as in rosin esters (DAPE), was performed to achieve the cellulose-rosin graft copolymers (EC-(g-DAPE)-g-PLMA) with UV absorption property. The chemical structure of cellulose-rosin graft copolymers was confirmed by FTIR, ¹H NMR and GPC. Thermodynamic performance analysis indicated that these EC-rosin graft copolymers showed better thermal stability than EC. Due to the synergistic hydrophobic interaction of rosin and the hydrophobic lauryl groups in PLMA, these graft copolymers showed excellent hydrophobic property, and the static contact angles were all above 90°. In addition, all the EC-rosin graft copolymers showed outstanding and stable UV absorption capability, and maintained excellent UV absorption capability after continuous UV-irradiation for 1 h or being heated to 100 °C for 0.5 h, which had potential application in UV absorption materials.

     

Graft polymers with macromonomers. I. Synthesis from methacrylate-terminated polystyrene

Pure graft polymers having uniform molecular weight polystyrene side chains were prepared by free radical copolymerization of methacrylate-terminated polystyrene macromonomers (MA-CROMER) with ethyl acrylate, butyl acrylate, or other suitable monomers. The MACROMER monomer was synthesized by living anionic polymerization under conditions that led to very narrow molecular weight distributions. Very effective end capping produced a material that was highly monofunctional. The graft copolymers were prepared by several techniques such as free radical solution polymerization, by aqueous suspension polymerization which produced beads, or by emulsion reactions which yielded stable latices. Polymerizations were reproducible. High conversion of the MACROMER monomer into pure graft polymers was achieved, and the product was contaminated with only a little homopolymer. The milled and molded phase-separated graft polymers had optical clarity and physical properties characteristic of polystyrene-reinforced triblock polymers. Compositions of 20-30% polystyrene were thermoplastic elastomers with good recovery. When polystyrene contents were increased, the graft products were strong, flexible thermoplastics with well defined yield strengths and increased permanent set. Copolymers of polystyrene macromers with acrylonitrile or vinyl chloride produced transparent polystyrene homopolymer-free graft polymer products having improved processing over polyacrylonitrile or poly(vinyl chloride) homopolymers.     

悬浮聚合法制备聚甲基丙烯酸甲酯微球的研究

以明胶为稳定剂采用悬浮聚合法合成了微米级聚甲基丙烯酸甲酯微球。通过研究搅拌速度、聚合温度及稳定剂用量,确定了较理想的合成工艺条件。