表面接枝改性对PET薄膜包装特性的影响

以PET薄膜为研究对象,首先运用过硫酸铵水相热分解使其表面羟基化,再在氧化-还原引发剂的存在下,引发丙烯酸单体自由基接枝聚合,在薄膜表面形成对环境湿度敏感的可溶胀的聚丙烯酸水凝胶层.研究结果表明:该表面接枝聚丙烯酸对材料的阻湿性没有显著影响;而干态下由于羧基间的氢键作用,薄膜氧气透过率,羧基接枝浓度的增加而减小;同时,改性后表面粗糙度增加,薄膜的静摩擦系数和动摩擦系数都随着羟基化处理时间的延长、表面[COOH]的增加而增加.     

MAA存在下VAc／BA核壳乳液聚合动力学研究

研究了功能性单体MAA的加入方式,乳化剂量和单体的加料速率等因素对MAA存在下VAc/BA核壳乳液聚合动力学的影响,同时探讨了动力学对胶粒形态变化和羧基分布的影响,研究表明,功能性单体MAA的加入方式不同会影响到壳层聚合阶段的溶胀、因而,使形成壳层的机理不同,乳化剂量和加料速率分别通过影响胶粒数和总体反应速率系数而对胶粒溶胀和壳层聚合反应产生影响。由于胶粒内聚合物浓度高、粘度大、因而胶粒形态变化受动力学影响甚大,羧基分布主要是由动力学确定的。     

表面接枝改性对聚乙烯薄膜阻隔性的影响

以PE包装膜为研究对象,首先通过过硫酸铵水相热分解使其表面羟基化,再在氧化-还原引发剂的存在下,引发丙烯酸单体自由基接枝聚合,在薄膜表面形成可溶胀的聚丙烯酸水凝胶层.研究结果表明,该表面接枝聚合反应对材料的阻水性没有显著影响;相反,由于干态下游离羧基间强烈的氢键作用,增加了O2分子透过的薄膜的阻力,薄膜氧气透过率随游离羧基浓度的增加而显著减小.     

Development of oligonucleotide microarray involving plasma polymerized acrylic acid

This paper presents the manufacturing of biochips by using the COOH- derived polymer coating deposited by plasma polymerization of acrylic acid. This technology is based on depositing a thin layer obtained by plasma polymerization of acrylic acid which allows a further covalent immobilization of biomolecules on glass substrates. The plasma power value was optimized to maximize the stability of plasma polymerized acrylic acid (PPAA) coatings in water, which has a very important role for such applications. In order to obtain a covalent immobilization of DNA probes on the PPAA coated surface, the activation protocol of carboxylic function was carried out with the help of N-Hydroxy Succinimide and 1-Ethyl-3-(3-DimethylAminopropyl) Carbodiimide. The efficiency of PPAA coated in microarray applications was compared with two types of commercial slides. Such surfaces have shown very interesting results in terms of relative density of attached DNA probe molecules and signal-to-background ratio measured for target DNA hybridization. Nonspecific DNA bonding measurements showed only a small amount of nonspecific physisorption between the DNA probe and the PPAA-activated surfaces. This work shows that the plasma polymerization technique can be successfully applied to produce a high-quality glass surface for the manufacturing of DNA arrays.     

超声波辅助纤维素系高吸水树脂的合成及表征

选用可生物降解的纤维素为基本骨架,利用硝酸铈铵作为引发剂处理纤维素,采用超声波辅助方法使其与丙烯酸发生接枝共聚反应,合成高吸水树脂.研究超声波功率、引发剂用量、丙烯酸与微晶纤维素的质量比、中和度、交联剂用量对树脂吸水倍率的影响,并对纤维素系高吸水树脂进行红外光谱和扫描电镜分析.结果表明,最佳工艺条件:超声波功率为500 W,引发剂用量为1.8 mL,丙烯酸与微晶纤维素的质量比为3.0:2.0,中和度为50％,交联剂质量分数为0.10％.此条件下制得的吸水树脂的吸蒸馏水倍率为486倍,吸自来水倍率为173倍.经红外光谱和扫描电子显微镜综合分析,证明超声波处理可以使得微晶纤维素表面发生变化,促进微晶纤维素与丙烯酸的固相接枝共聚,合成的纤维素系高吸水树脂保留了微晶纤维素分子骨架和聚丙烯酸各自的特性,在纤维素大分子表面和无定型区引发了接枝聚合.     

高吸水性树脂的微波辐射合成工艺及性能研究

针对目前高吸水性树脂合成中存在的问题，采用微波加热提供反应所需热量，以淀粉为原料，过硫酸钾为引发剂，进行丙烯酸接枝共聚反应，开展了高吸水性树脂的微波辐射合成工艺及性能研究，在最佳条件下合成了吸水率为753g/g的高吸水性树脂，性能测试结果表明，该树脂具有良好的吸水和保水性能。本工艺较传统加热合成方法节省时间数10倍，操作条件易于控制，无“三废”排放，是合成高吸水性树脂的清洁生产工艺。     

UV固化型丙烯酸酯压敏胶的制备及表征

介绍了用BPO为引发剂、乙酸乙酯为溶剂、丙烯酸丁酯(BA)为粘性单体、乙酸乙烯酯(VAc)为内聚单体、丙烯酸(AA)为改性单体三元共聚合成UV固化型丙烯酸酯压敏胶的方法。研究了该压敏胶中各组分和反应条件对其物理-化学性能的影响,得出较优的制备条件是温度为84℃、反应时间为8h、其中单体加入量比为BA:VAc:AA=9:6:4、引发剂总用量为0.45%(wt),并用红外光谱仪、示差扫描量热仪对其合成的压敏胶进行了表征。     

Investigation of deposition rate and structure of pulse DC plasma polymers

In this study, hydrophobic plasma polymer films were prepared from perfluorohexane with saturated linear structure and octafluorotoluene with a cyclic unsaturated structure. Hydrophilic plasma polymer film was prepared from acrylic acid with an unsaturated linear structure. The film deposition rates were compared through in-situ laser interferometer measurement and correlated them with the precursor structure and the deposition parameters. The chemical structure and the surface energy of the films were also investigated with FTIR and contact angle measurement. The results showed that the deposition rate increased with the discharge power. Otherwise, the deposition rate relied on the structure of the precursors to a large extent. The deposition rate of octafluorotoluene is 7 times the deposition rate of perfluorohexane and 5 times the deposition rate of acrylic acid at the same deposition parameters. So a high deposition rate could be obtained for the precursors with cyclic and unsaturated structures. For the pulse discharge of acrylic acid, there existed a maximum deposition rate for a certain pulse frequency. But it was found that the pulse frequency had greater effects on the structure of the plasma films than on the deposition rate. As the pulse frequency decreased, more CHO and O---C=O groups were found in the deposited film of acrylic acid. And the pulse discharge at low power could keep more aromatic ring in octafluorotoluene plasma film than continuous discharge at high power. This explained the phenomenon that the surface energy of octafluorotoluene plasma film deposited by the low power pulse discharge was lower than that of the film deposited by the high power continuous discharge and showed to be more hydrophobic.     

磷酸胆碱表面改性涤纶材料及抗凝血性研究

采用氧等离子体预处理涤纶材料（聚对苯二甲酸乙二醇酯,PET）表面,并通过紫外辐照在其表面接枝聚合丙烯酸,以接枝聚丙烯酸链中的羧基为反应位点,通过原子转移自由基聚合在PET表面进一步固定磷酸胆碱聚合物。经漫反射红外光谱及X射线光电子能谱分析测试表明,涤纶薄膜表面成功地固定了磷酸胆碱聚合物。经磷酸胆碱聚合物改性的涤纶表面亲水性得到改善,体外抗凝血性评价表明,固定磷酸胆碱的PET表面能够有效地抑制纤维蛋白原分子的变性,降低血小板粘附和激活。     

高含量丙烯酸膨润土/聚丙烯酸钠高吸水性复合材料的研究Ⅰ:制备工艺与形貌

通过特殊工艺将丙烯酸膨润土(简称ABT)和丙烯酸钠单体采用溶液聚合法制备出高含量丙烯酸膨润土/聚丙烯酸钠高吸水性复合材料(简称HABT/PAA).SEM考察材料的形貌得知,ABT以20～30nm的尺寸较均匀、无序地分散在聚合物基体中,且与聚合物有很好的相容性.对合成工艺进行了优化得到较优的工艺:ABT用量为单体质量的30％(质量分数),交联剂用量为单体质量的0.3％(质量分数),引发剂用量为单体质量的1.1％(质量分数),体系总水量为单体质量的340％(质量分数),中和度为64％,在此条件下,材料吸附去离子水的能力为1103g/g.同时,HABT/PAA的保水性能较聚丙烯酸钠(PAA)好.     

铝合金阳极化氟碳保护涂料的研究

现有阳极化保护涂料普遍存在耐酸性和弹性差的缺点,为此,采用丙烯酸含氟单体、丙烯酸单体、丁苯橡胶(SBS)通过自由基共聚的方法合成了氟碳树脂,获得了一种耐酸、高弹的铝合金阳极化涂料.对树脂的红外光谱分析表明,丙烯酸含氟单体参与了共聚反应.通过原位共聚的方法引入了纳米二氧化钛.随着氟含量的提高,涂层的耐甲乙酮擦拭性、耐酸性、耐沸水附着力、耐人工老化等性能提高,当氟含量超过6%时涂层的附着力下降;纳米TiO2的引入使涂层的耐盐雾性、抗拉强度明显提高;当固体含量为25%,msbs/m单体=4%时,丁苯橡胶的引入,涂层在柔韧性、伸长率、耐磨性、冲击强度方面均有所提高.氟碳丙烯酸保护涂料能够满足铝合金阳极化绝缘保护的要求.     

Multi-layered plasma-polymerized chips for SPR-based detection

The surface functionalization of a noble metal is crucial in a surface plasmon resonance-based biomolecular detection system because the interfacial coating must retain the activity of immobilized biomolecules while enhancing the optimal loading. We present here a one-step, room-temperature, high-speed, gas-phase plasma polymerization process for functionalizing gold substrates using siloxane as an adhesion layer and acrylic acid as a functional layer. Siloxane- and thiol-based coatings were compared for their performance as adhesion and the interfacial layer for subsequent functionalization. An in situ sequential deposition of siloxane and acrylic acid resulted in a 7-fold increase in carboxylic functionality surfacial content compared to films deposited with thiol-containing precursors. Grading of the layer composition achieved as a consequence of ion-induced mixing on the surface coating under the application of the plasma is confirmed through secondary ion mass spectroscopic studies. DNA hybridization assays were demonstrated on gold/glass substrates using surface plasmon enhanced ellipsometry and the applicability of this coating for protein immunoassays were demonstrated with plasma functionalized gold/plastic substrates in Biacore 3000 SPR instrument.     

聚丙烯酸-甲基丙烯酸-丙烯酰胺P(AA-MA-AM)三元共聚物的合成及其吸湿性能研究

以丙烯酸、丙烯酰胺和甲基丙烯酸为单体,N,N’-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂制备P(AA-AM-MA)高分子吸湿材料。系统研究单体浓度、单体配比等因素对其吸湿性能影响。根据正交实验,P(AA-AM-MA)最高吸湿率达0.95g/g。应用Sigma Stat 3.5进行多元线性回归分析得各因素与吸湿率的数学关联式,吸湿量直观分析表明,六因素影响吸湿性的主次顺序:脲含量>中和度>单体浓度>单体配比>交联剂浓度>引发剂浓度。     

Plasma polymer coated surfaces for serum-free culture of limbal epithelium for ocular surface disease

The potential use of plasma polymer coatings as substrates for serum-free expansion of limbal epithelial cells was investigated. Preliminary studies using a human corneal epithelial cell line showed that acrylic acid-coated surfaces performed better than allyl amine and allyl alcohol coated surfaces in terms of cell metabolic activity and confluence as assessed using the MTT assay. Subsequently, the proliferation and maturity of primary human limbal epithelial cells in co-culture with growth arrested 3T3 fibroblasts on a range of acrylic acid plasma coated surfaces, octadiene plasma coated surfaces and tissue culture plastic was investigated using MTT and cytokeratin 3 immunostaining. The cells performed better in the presence of serum on all surfaces. However, the acrylic acid coated surfaces successfully sustained a serum-free fibroblast/epithelial cell co-culture. The metabolic activity of the epithelial cells was superior on the acrylic acid coated surfaces than on tissue culture plastic in serum-free conditions and their levels of differentiation were not significantly higher than in the presence of serum. These results suggest that these surfaces can be used successfully for the serum-free expansion of human limbal epithelial cells.     

海藻接枝丙烯酸高吸水性树脂的制备及性能研究

采用海藻为原料与丙烯酸接枝共聚制备了高吸水性树脂。通过红外光谱(FT-IR)分析了产物的结构。考查了丙烯酸中和度、丙烯酸用量、引发剂和交联剂的用量以及反应温度等各因素对产物吸水率的影响。结果表明,所得树脂的吸水率可达618g/g,吸盐水率(0.9%的NaCl水溶液)达到120g/g,其吸水速率适中,热稳定性和在室温下的保水性均较好,是一种新的环保型高吸水性树脂。FT-IR初步表明了丙烯酸与海藻的接枝聚合作用。     

Preparation of a reticulated polyurethane foam grafted with poly(acrylic acid) through atmospheric pressure plasma treatment and its lysozyme immobilization

We successfully introduced peroxide groups onto the surface of PU(Polyurethane) foam(10 PPI) through one atmospheric pressure plasma treatment and sequentially grafted PAAc(poly(acrylic acid)) on the surface of PU through radical copolymerization. The plasma treatment can generate large amount of peroxides on the surface of PU foam and the peroxide groups act as initiators for further grafting of PAAc in the monomer solution. To introduce large amount of peroxides on the surface of PU foam, we studied the effect of plasma rf-power and treatment time on the maximum grafting of PAAc. Through this study, we found that the optimum plasma treatment condition was the rf-power of 100 W and the treatment time of 100 s. On the other hand, we also studied the effect of graft reaction conditions such as temperature, monomer concentration and reaction time on the change of grafting degree (GD). The GD increased with increasing temperature and increased with reaction time before it leveled off at 3 h after reaction started. At low concentration of AAc, the GD was very low but it showed a maximum at the monomer concentration between 60 and 70%. The surface of the modified PU foam was qualitatively and quantitatively analyzed through the use of FT-IR and weight measurement, respectively. We also observed the surface change before and after plasma induced graft co-polymerization through photo and SEM analysis. Finally, we confirmed that the PU foams grafted with PAAc successfully immobilized lysozyme and other proteins from hen egg white.     

Plasma modification of polyacrylonitrile ultrafiltration membrane

Polyacrylonitrile (PAN) ultrafiltration (UF) membranes were modified by plasma treatments and plasma polymerization. Influences of plasma modifications on membrane characteristics were investigated. The obtained results indicated that plasma treatments using non-polymer-forming plasma gases such as Ar, He and O₂ led to the increase of membrane surface hydrophilicity and membrane permeability. By using O₂ plasma treatment, UF property of PAN membranes could be improved with the enhancement of membrane flux meanwhile its albumin rejection was almost maintained. The experimental results also showed that plasma polymerization using acrylic acid vapor as monomer and PAN UF membrane as a substrate led to the formation of reverse osmosis membrane due to the deposition of plasma polymer layer onto substrate membrane surfaces. Plasma techniques can control membrane pore size and have a potential to improve the membrane characteristics by using their advantages.     

Mechanical properties and rheology of polyalkenoate cements using various low-cost fillers

Low-cost polyalkenoate cements analogous to dental cements, i.e., cements based on polymers of acrylic acid crosslinked via bridging metal cations, were developed with a goal of producing a more flexible alternative to Portland cement. Economic constraints necessitated the replacement of the acid-degradable glass normally used in dental cements; the purpose of the glass is to provide both a source of polyvalent cations for crosslinking and solid filler for a composite material. The dual functionality of the powdered glass was accomplished via the use of manganese tetraoxide as the filler and aluminum chloride as the cation source for the ionic crosslinks. Unlike dental cements that have a gel-like consistency before setting, low viscosity cements were produced by using acrylic acid monomer rather than low-molecular weight poly(acrylic acid). Mechanical and rheological properties were used to monitor cement characteristics. Because of the large number of formulation variables, a design of experiments (DOE) approach was used. DOE helped narrow the search for formulations that would result in hardened cements and find the optimal set of ingredients that led to cements with the best properties given the economic constraints on the ingredients. Rheology was adjusted to match that of Portland cement by altering the filler volume fraction, which was very effective since the rheology depended strongly on that variable. The most pertinent independent variables for the mechanical properties were the curing time and monomer/cation ratio in the ranges tested; however, the monomer/water ratio was fixed at the minimum level possible and not increased because of economic considerations. The best materials produced in terms of mechanical properties resulted when acrylic acid monomer was partially replaced by N,N′-methylenebisacrylamide; this substitution resulted in a stronger and tougher cement. An erratum to this article can be found at     

窄分子量分布的乙酸乙烯酯聚合物的制备

以丙烯酸为调聚单体、偶氮二异丁腈为引发剂、甲醇为溶剂进行乙酸乙烯酯溶液聚合。通过聚合转化率和凝胶渗透色谱的测定,研究了聚合过程和所制备聚合物的分子量及其分布,以及丙烯酸对聚合物分子量分布的影响;进一步探讨了反应装置的安装及结构对聚合反应的影响。结果表明,适当引入丙烯酸,当丙烯酸/乙酸乙烯酯的摩尔比为3/100,并采用密封冷凝搅拌装置,反应5 h,既可确保较高聚合转化率,又可获得窄分子量分布的聚合产物。     

Functionalization of silicone rubber for the covalent immobilization of fibronectin

Surface modification techniques were employed in order to provide functionalized silicone rubber with enhanced cytocompatibility. Acrylic acid (AAc), methacrylic acid (MAAc) and glycidylmethacrylate (GMA) were graft-co-polymerized onto the surface of silicone induced by an argon plasma and thermal initiation. The polymerizations were carried out in solution, in the case of acrylic acid a vapor phase graft-co-polymerization subsequent to argon plasma activation was carried out as well. Human fibronectin (hFn), which acts as a cell adhesion mediator for fibroblasts, was immobilized by making use of the generated carboxylic or epoxy groups, respectively. Surface analysis was accomplished by means of X-ray photoelectron spectroscopy (XPS), infrared spectroscopy in attenuated total reflection mode (IR-ATR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and dynamic contact angle measurements using the Wilhelmy-plate method. The amount of immobilized active hFn was semiquantified by enzyme-linked immunosorbent assay (ELISA) using a structure-specific antibody against the cell-binding domain of hFn. In vitro testing showed a remarkable difference between surfaces exposing adsorbed-only and surfaces with covalently immobilized hFn. © 2001 Kluwer Academic Publishers