紫外辐照接枝HEMA改性血液过滤用PBT无纺布的研究

研究了在紫外辐照条件下,以二苯甲酮(BP)为光敏剂,以甲基丙烯酸羟乙酯(HEMA)作为表面接枝物来改性血液过滤用聚对苯二甲酸丁二醇酯(PBT)无纺布,并对接枝改性后PBT进行了红外分析、扫描电镜观察、亲水性能测试.结果显示:红外图谱证实了HEMA在紫外辐照和光敏剂BP的引发条件下成功接枝到PBT 无纺布纤维表面,光敏剂...     

活性聚合与巯基-烯化学结合构造表面抗污材料

本文利用链转移试剂(Chain Transfer Agent,CTA)依次控制N,N-二甲基丙烯酰胺(DMA)、甲基丙烯酸烯丙基酯(AMA)进行可逆-加成链转移活性可控聚合反应(RAFT),得到末端带有活性双键的二嵌段聚合物聚N,N-二甲基丙烯酰胺-b-聚甲基丙烯酸烯丙基酯(PDMA-PAMA)。该活性聚合物所含双键与乙烯基硅氧烷改性后的基体材料在适量的多巯基小分子促进下发生巯基-烯烃点击化学反应后接枝到基体材料表面。改性前后材料表面接触角测试表明,亲水性改性后的玻璃表面接触角明显小于未改性的玻璃表面,说明改性后的玻璃表面已接枝上亲水性基团,表面亲水获得改善。这种将RAFT与巯基-烯反应结合并应用于材料表面接枝改性的方法,可潜在应用于高端抗污涂层制备领域。     

水性聚氨酯的环氧共聚改性研究

采用环氧树脂(EP)对水性聚氨酯(WPU)进行改性,通过自乳化法合成了EP改性的WPU.探讨了EP的加入方式、用量以及亲水剂等因素对WPU乳液和涂膜性能的影响.结果表明交联反应显著提高了乳液膜的硬度及其耐水性、力学性能.用二羟甲基丁酸(DMBA)替代二羟甲基丙酸(DMPA)作亲水剂制备的改性WPU乳液,其乳液性能、涂膜的硬度及其耐水性能更佳.     

丙烯酸改性氯化聚丙烯乳液的合成与性能

采用溶液法用含亲水单元的丙烯酸混合单体与氯化聚丙烯进行自由基接枝共聚反应,制得丙烯酸改性氯化聚丙烯,将其中和后加水分散即得丙烯酸改性氯化聚丙烯乳液.用傅罩叶红外光谱对产物进行了表征.研究了丙烯酸混合单体浓度、中和度和甲基丙烯酸含量对乳液性能的影响,当丙烯酸混合单体与氯化聚丙烯的质量比为0.5-1.5、甲基丙烯酸含量为15%-20%(占单体总量的质量比)、中和度为80%～120%时,制备的水性乳液具有良好的稳定性和水分散性,乳液涂膜对聚丙烯板具有很好的附着力和光泽.     

聚偏氟乙烯接枝改性的研究进展

叙述了聚偏氟乙烯(PVDF)接枝改性的主要方法及其改性树脂的应用领域,特别介绍了在超滤膜亲水改性方面的应用研究,通过接枝改性改善了滤膜的耐污染性,赋予膜材料新的功能,扩大了其应用领域。但目前接枝率偏低,接枝均匀性不佳,改性单体的自聚难以避免,尽量减少或消除单体的自聚一直是接枝反应的难点。进一步开发出性能优异的PVDF功能材料和亲水性超滤膜是重点研究的方向。     

羧甲基纤维素接枝聚磺甲基化丙烯酰胺的制备及其吸附性能的研究

用化学改性羧甲基纤维素接枝聚丙烯酰胺(CMC-g-PAM)树脂制备了羧甲基纤维素接枝聚磺甲基化丙烯酰胺(CMC-g-SPAM)吸水树脂。采用静态法测定该强阴离子性吸水树脂对重金属离子的去除条件和去除效果。实验结果表明,该树脂对铅离子有很好的吸附脱除性能,脱除率可达95％,1g树脂可吸附2．7mg铅。X射线光电子能谱(XPS)等微观结构测试表明,吸附后重金属铅离子在吸水树脂上聚集存在,为非晶态。     

新型快干水性丙烯酸改性环氧酯树脂的研制

用丁烯酸改性环氧酯树脂,采用接枝共聚的方法引入亲水单体,再用丙烯酸酯类单体对其进行改性,制得新型快干水性丙烯酸改性环氧酯树脂。研究了改性环氧酯树脂、引发剂(过氧化苯甲酰)、丙烯酸单体的用量和接枝共聚合时的反应温度和反应时间这5个因素对树脂性能的影响。     

硅橡胶的表面接枝改性及抑菌性能研究

通过使用复配交联剂制备室温硫化硅橡胶,采用等离子体在硅橡胶表面引入活性基团,进一步利用表面引发原子转移自由基聚合对硅橡胶进行表面接枝聚丙烯酰胺改性。利用衰减全反射傅里叶变换红外光谱、接触角、XPS、SEM等对改性前后硅橡胶的表面结构、组成、形貌和性能进行表征;并利用细菌黏附实验对比研究改性前后硅橡胶表面的细菌黏附性。结果表明,接枝改性后的硅橡胶,其表面由108.5°的疏水表面变为49.5°的亲水表面,硅橡胶表面细菌黏附量最高可降低98.7%。     

一种新型阳离子聚丙烯酰胺的合成及表征

将具有球型分子结构的超支化聚合物接枝到阳离子聚丙烯酰胺上,目的是当用阳离子聚丙烯酰胺处理油田污水时,抑制分子的卷曲速度,提高絮凝性能。作者首先以二甲基二烯丙基氯化铵(DMDAAC)、丙烯酰胺(AM)和丙烯酸(AA)为单体,聚合得阳离子聚丙烯酰胺,该聚合物具有线型分子结构。再以甲基丙烯酰氧乙基三甲基氯化铵(DMC)与端部氨基的超支化聚合物反应,得到端部带有阳离子的超支化聚合物,该聚合物具有类似球型的分子结构。然后将阳离子超支化聚合物接枝到线形阳离子聚丙烯酰胺上,得到一种接枝改性的阳离子聚丙烯酰胺。用红外分光光度仪分析证明得到了预期的产物结构,并测定了产物的特性粘度、阳离子度。     

在明胶上接枝聚丙烯酰胺

合成了不同配比的明胶/聚丙烯酰胺接枝共聚物,测定了该接枝共聚产物溶液的相对粘度,并与明胶/聚丙烯酰胺共混物溶液的相对粘度进行了对比,间接证明了接枝物的生成。该接枝物仍具有较明显的等电点。     

Surface structure and adhesive properties of biaxially oriented polypropylene film grafted with poly(acrylic amide) using corona discharge

Corona discharge was explored as a means of forming chemically active sites on the surface of biaxially oriented polypropylene (BOPP) film. The active species formed in air was used to induce graft copolymerization of acrylic amide (AAM) in aqueous solution. The surface structure, hydrophilicity and adhesion of the grafted BOPP film were characterized by the extent of grafting, electron spectroscopy for chemical analysis (ESCA), scanning electron microscopy (SEM), peel strength and contact angle measurements. Surface graft‐copolymerization of AAM onto BOPP film by corona discharge in air can be carried out with high efficiency. With increasing copolymerization time, the degree of grafting of AAM onto BOPP increases. The degree of grafting achieved a relatively high value of 2.13 wt% for the conditions of 1 min corona discharge and a copolymerization reaction time of 2.5 hr in 20% AAM aqueous solution at 70°C. After corona discharge grafting, the contact angle of water on the BOPP film decreased and the peel strength increased compared with those for ungrafted BOPP film. The hydrophilicity and adhesion of BOPP were improved by surface graft copolymerization with AAM induced by corona discharge.     

RTV表面紫外光接枝HEMA的研究

采用液相紫外光接枝方法,研究了室温硫化型硅橡胶与甲基丙烯酸β羟乙酯的接枝反应。利用红外光谱、扫描电镜对接枝物进行了表征,并讨论了引发剂用量、辐照时间对接枝率和接触角的影响,以及不同接枝率下接枝膜的吸水性能。结果表明:引发剂质量分数为为0.25%,辐照时间为2 min时,接枝效果较好;接枝后硅橡胶的亲水性得到明显改善。     

羊毛角蛋白液涂覆处理涤纶的亲水性研究

利用三羧乙基膦(TCEP)和亚硫酸氢钠溶解羊毛制备羊毛角蛋白溶液;采用羊毛角蛋白液涂覆处理涤纶,改善涤纶的亲水性,结果表明:采用体积分数为10%的羊毛角蛋白液涂覆处理涤纶织物,织物平均增重率大于9%,织物的回潮率由0.57%提高到7.16%.吸湿性明显改善;采用TG酶交联角蛋白液涂覆处理织物,可改善其耐洗性;TC酶交联角蛋白的最佳工艺为:TG酶用量1 g,交联时间5 h,交联液pH值为7;经扫描电镜观察和X射线光电子能谱分析,羊毛角蛋白对涤纶有很好的粘附     

Effect of Saccharides Coating on Antibacterial Potential and Drug Loading and Releasing Capability of Plasma Treated Polylactic Acid Films

More than half of the hospital-associated infections worldwide are related to the adhesion of bacteria cells to biomedical devices and implants. To prevent these infections, it is crucial to modify biomaterial surfaces to develop the antibacterial property. In this study, chitosan (CS) and chondroitin sulfate (ChS) were chosen as antibacterial coating materials on polylactic acid (PLA) surfaces. Plasma-treated PLA surfaces were coated with CS either direct coating method or the carbodiimide coupling method. As a next step for the combined saccharide coating, CS grafted samples were immersed in ChS solution, which resulted in the polyelectrolyte complex (PEC) formation. Also in this experiment, to test the drug loading and releasing efficiency of the thin film coatings, CS grafted samples were immersed into lomefloxacin-containing ChS solution. The successful modifications were confirmed by elemental composition analysis (XPS), surface topography images (SEM), and hydrophilicity change (contact angle measurements). The carbodiimide coupling resulted in higher CS grafting on the PLA surface. The coatings with the PEC formation between CS-ChS showed improved activity against the bacteria strains than the separate coatings. Moreover, these interactions increased the lomefloxacin amount adhered to the film coatings and extended the drug release profile. Finally, the zone of inhibition test confirmed that the CS-ChS coating showed a contact killing mechanism while drug-loaded films have a dual killing mechanism, which includes contact, and release killing.     

涂料用有机硅改性丙烯酸树脂的合成与研究

以溶液聚合法合成了有机硅改性丙烯酸树脂,选择不同种类的硅单体进行实验,研究了硅单体用量对涂膜吸水率的影响以及不同软硬丙烯酸类单体比例对涂膜柔韧性及吸水率的影响,并对涂膜进行了红外分析和扫描电镜分析。结果表明：由接枝反应改性的有机硅丙烯酸酯涂料具有优良的性能。     

Photografting polymerization of polyacrylamide on PHBV films (I)

Photografting polymerization of polyacrylamide (PAM) onto poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) films using benzophenone as photoinitiator was studied. The morphology and structure of the grafted PHBV film were characterized by Fourier transformed infrared spectroscopy (FTIR) with attenuated total reflectance (ATR) and scanning electron microscope (SEM) with energy dispersive X‐ray spectrometer (EDX). The grafting percentage and grafting efficiency of the grafted PHBV film went up with the increase of acrylamide concentration and irradiation time. It was observed that photografting polymerization of PAM was not only limited to the film surface, but also in situ occurred inside the film to form the pore microstructure. Sheep bone marrow stromal cell studies showed that MSCs cells attachment efficiency on the grafted PHBV films increased and cells grew well. These results demonstrated the potentiality of PAM‐photografting PHBV in medical applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104, 4088–4095, 2007     

Antigraffiti polyurethane coating containing fluorocarbon side chains grafted polymethylsiloxane

The novel polymethylsiloxane grafted by fluorocarbon side chains was synthesized via hydrosilylation reaction of polymethylhydrosiloxane (PMHS) with 2,2,3,4,4,4-hexafluorobutyl acrylate (HFBA) in the presence of Karstedt’s catalyst. The reaction factors of reaction temperature, reaction time, catalyst dosage, solvent dosage, and molar ratio of the reactants were investigated through orthogonal experiments. Under optimal conditions, the grafting ratio of HFBA to PMHS reached 91.6%. The structure of the grafted polymer was characterized by FTIR and ¹H NMR spectra. The synthesized polymer was incorporated into two-component polyurethane coating formulations as an additive to prepare antigraffiti coatings. After curing, the contact angle measurement was performed and the results showed that surface free energy of the coating film decreased dramatically from 30.7 to 21.4 mJ/m². The inks of permanent markers cannot spread readily on the coating film and can be removed easily, indicating that the incorporation of the synthesized polymer endowed the coating with admirable antigraffiti performance. XPS analysis revealed that atomic concentrations of silicon and fluorine near the surface (about 10 nm) were much higher than deeper within the film (about 100 nm), suggesting that these two elements had a strong migration tendency toward the coating–air interface. AFM measurement showed that the inclusion of synthesized polymer in coating did not affect the surface roughness of the film.     

低温固化环氧粉末涂料制备及性能研究

通过转矩流变仪用E-12型环氧树脂和TC-125固化剂及其他助剂在90℃下熔融混合10min,然后在平板硫化机上冷压3min,最后经过球磨机粉碎制得环氧粉末涂料。制得的粉末涂料和漆膜经过差示扫描量热法和红外光谱分析．并讨论了固化剂用量、升温速率等对涂料性能的影响。结果表明：该粉末涂料可实现低温固化,固化条件为120℃下恒温固化35min;固化剂用量为28％时,涂膜的各项物理性能良好。     

紫外光固化二氧化硅/丙烯酸酯亲水杂化薄膜

紫外光照射下制备了用于改善玻璃表面亲水性的二氧化硅/丙烯酸酯透明杂化薄膜,其水接触角小于5°,具有优异的亲水性。讨论了反应时间、反应温度、丙烯酸羟丙酯用量和正丙醇用量与薄膜亲水性的关系。通过SEM对薄膜表面形貌进行了研究,发现薄膜具有多孔结构,SiO₂溶胶粒子均匀分布在膜层中。研究表明,以硅溶胶（ml）与丙烯酸羟丙酯（mol）配比为50∶0.15在40℃时反应1 h制备杂化溶胶,且涂膜液用20%（质量）正丙醇稀释时所制备的杂化薄膜亲水性最好。     

Comparison of two approaches to grafting hydrophilic polymer chains onto polysulfone films

To reduce the surface protein adsorption of polysulfone (PSf) film, we improved the hydrophilicity of this film by photochemical grafting of methoxypoly (ethylene glycol) (MPEG) derivatives on its surface. Grafting was achieved with both the simultaneous method and the sequential method. Surface analysis of the grafted film by X‐ray photoelectron spectroscopy (XPS) revealed that the PEG chains had successfully grafted onto the surface of the film. The grafting efficiencies by simultaneous and sequential methods were 20.8% and 10.2%, respectively. With an atomic force microscope (AFM), the surface topography of PEG‐grafted films by these two methods was compared. Static water contact angle measurement indicated that the surface hydrophilicity of the film had been improved. Protein adsorption measurement showed that the surface protein adsorption of the modified film was significantly reduced compared with that of the unmodified PSf film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3818–3826, 2007