酸化处理多壁碳纳米管/氰酸酯树脂复合材料性能

采用酸化处理的多壁碳纳米管（MWCNTs）增强双酚A型氰酸酯-酚醛型氰酸酯（BCE-NCE）树脂。通过SEM、TEM对MWCNTs/BCE-NCE树脂复合材料微观结构进行表征,利用DSC、DMA和TG/DTA对MWCNTs/BCE-NCE树脂复合材料热性能进行研究,采用电子拉力机对MWCNTs/BCE-NCE树脂复合材料力学性能进行测试,采用谐振腔法对MWCNTs/BCE-NCE树脂复合材料介电性能进行测试。结果表明,混酸处理过的MWCNTs在BCE-NCE树脂基体中的分散效果较好。MWCNTs对BCE-NCE树脂热力学性能影响不大,当MWCNTs添加量为0.8wt%时,BCE-NCE树脂玻璃化转变温度（T_g）从298℃下降到285℃,但仍维持较高水平。当MWCNTs添加量为0.6wt%时,MWCNTs/BCE-NCE树脂复合材料冲击强度为11.40 kJ/m²,提高了40.7%。MWCNTs的加入增加了BCE-NCE树脂介电常数和介电损耗,当MWCNTs添加量为0.8wt%、频率为1 GHz时,MWCNTs/BCE-NCE树脂复合材料介电常数为5.1,介电损耗为0.032。因此,MWCNTs/BCE-NCE树脂复合材料未来可在耐高温复合材料和电子等行业应用。     

低压片状模塑料中结晶树脂的增稠机理探讨

本研究合成了熔点为81.3℃的结晶树脂,然后通过改变结晶树脂的加入含量,考察了增稠效果,并对结晶树脂增稠的机理进行了探讨。研究表明,当结晶树脂质量百分含量为5%时,结晶树脂的增稠效果最好;而在结晶树脂的增稠过程中,有三种作用:溶胀、氢键和诱导结晶作用,其中溶胀和诱导结晶作用最为明显。该研究为LPM C生产工艺的制定提供了理论依据。     

可剥离防护涂料的研究进展

介绍了国内外可剥离涂料的常用成膜物质,包括聚氨酯树脂、聚苯乙烯树脂、聚乙烯醇、有机硅、聚丁基二烯、氯醋树脂、乙基纤维素、乙烯基高分子树脂、丙烯酸树脂及其共聚物等,讨论了以它们为成膜物质时所制备的可剥离涂料的优劣性,并对可剥离涂料存在的问题和发展方向进行了展望。     

羧基化聚丙烯酸酯接枝邻甲酚环氧丙烯酸树脂的合成

采用JF-220环氧树脂和丙烯酸为原料,合成了邻甲酚环氧丙烯酸(JFA)树脂,并将JFA树脂和羧基化聚丙烯酸酯进一步反应制备羧基化聚丙烯酸酯接枝邻甲酚环氧丙烯酸(CA JFA)树脂,研究了催化剂、阻聚剂和反应温度对合成反应的影响。结果表明:催化剂三苯基膦和阻聚剂对羟基苯甲醚用量分别为羧基的0.80%和0.06%,温度为90℃~100℃反应4 h,有利于JFA树脂和CA JFA树脂的合成。同时对JF-220树脂,JFA树脂和CA JFA树脂的结构进行了IR表征。     

绿色耐盐性淀粉基高吸水性树脂的制备及抑尘效果研究

以淀粉、丙烯酸和丙烯酰胺为主要原料,水溶液聚合法制备了绿色高吸水性树脂。考察了中和度、引发剂用量、交联剂用量、单体质量比及淀粉用量等实验条件对吸水率的影响。最佳条件下制备的树脂在蒸馏水和自来水中的吸水率分别为815.4和208.7g/g。对树脂的耐蒸发性与抑尘性进行了研究,结果表明树脂对黄土有较好的抑尘效果,可作为抑尘剂使用。采用红外光谱法对树脂结构进行了分析。     

F_(2314)基常温固化涂料的改性研究

用改性树脂对F2314树脂涂料进行改性,研究不同的改性树脂用量和固化剂的种类以及其用量对F2314树脂涂料涂膜的影响,并对共混膜进行了表征。结果表明,F2314树脂与改性树脂的共混比为8∶2而且固化剂的用量为改性树脂的15%时,涂膜的附着力、硬度达到了最大值,而且外观也很平整;红外光谱测试表明,F2314树脂与改性树脂之间发生了相互作用;共混膜的SEM照片可见涂膜表面是网状结构,类似半互穿网络聚合物(IPN)结构。     

高吸水性树脂——淀粉-丙烯酸钠接枝共聚物的合成及性能研究EI

以淀粉和丙烯酸钠为原料,选择过硫酸铵为引发剂,环氧氯丙烷为交联剂进行接枝共聚,获得了吸水量1000倍以上的高吸水性树脂。对该树脂进行了结构、性能、以及在农业上使用的研究和分析,并得到了一些初步结论。     

丙烯酰胺/凹凸棒复合吸水性树脂的制备及溶胀行为

采用水溶液聚合法制备了丙烯酰胺／凹凸棒复合吸水性树脂,考察了凹凸棒含量、单体浓度、交联剂含量和引发剂含量对树脂吸水性能的影响,并通过FT-IR和SEM对接枝反应机理和材料的表面形貌进行了表征;同时时树脂在电解质溶液中的溶胀行为进行了研究。结果表明,当凹凸棒质量分数为10％时,复合吸水性树脂在蒸馏水和0．9％NaCl溶液中的吸水倍率分别达到了2645g／g和112g／g,树脂耐盐性能明显提高。     

SSS单体引入半纤维素-AA系高吸水树脂的吸水性探讨

以半纤维素为骨架,分别制备半纤维素-AA高吸水树脂和半纤维素-AA-SSS共聚高吸水树脂。考察了SSS用量对共聚树脂吸水率的影响,通过红外光谱仪及扫描电镜对树脂结构进行了分析,并对2种树脂的吸水率、耐盐性及吸水速率进行了对比分析。结果表明:引入少量SSS单体可显著改善树脂的表面结构,降低其对盐溶液(NaCl溶液)的敏感程度,大幅提高吸水率和吸盐水率,同时,可使树脂吸水速率提高近1倍。     

AG80/DDS/PEK树脂改性体系的关键性能研究

以4,4’-二氨基二苯甲烷(AG80)为基体树脂,以4,4’-二氨基二苯砜(DDS)为固化剂,制备了树脂体系并进行改性研究。对树脂粘度、凝胶时间、DSC及浇注体力学性能等方面进行了测试。结果表明,通过树脂改性可以增加树脂体系的粘度,减少树脂体系的凝胶时间,树脂体系浇注体的力学性能,随着改性填料的加入呈现出先增强后减小的规律。     

聚合反应条件对甲基丙烯酸缩水甘油酯/丙烯酸丁酯乳液共聚体系凝胶的影响

将丙烯酸丁酯（BA）与甲基丙烯酸缩水甘油酯（GMA）进行乳液共聚合以制备环氧型聚丙烯酸酯橡胶（ACM）,通过对ACM中凝胶含量及环氧基开环率的对比研究,探讨了不同反应条件对凝胶含量的影响。结果表明,在反应体系中加入20%的第二单体丙烯酸乙酯（EA）、选择复合引发体系、反应温度控制在30℃以及在反应体系对单体需求处于饥饿...     

Densities, Excess Volumes, and Partial Molar Volumes of m-Xylene+Ethyl Acrylate, +Butyl Acrylate, +Methyl Methacrylate, and +Styrene at 298.15 K

Densities of the binary systems of m-xylene with ethyl acrylate, butyl acrylate, methyl methacrylate, and styrene have been measured as a function of composition, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess volumes were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. The excess volumes are positive for the binaries of m-xylene with methyl methacrylate, ethyl acrylate, and styrene. The excess volumes for the m-xylene+butyl acrylate system are positive for solvent (m-xylene) concentrations below 0.3 mole fraction and negative above this concentration.     

聚丙烯酸酯改性环氧树脂的力学性能

通过丙烯酸乙酯(EA)和丙烯酸丁酯(BA)在环氧树脂中原位聚合,制备了聚丙烯酸酯改性的缩水甘油醚双酚A(DGEBA)-甲基四氢苯酐(MeTHPA)环氧树脂体系。原位聚合形成的聚丙烯酸酯在环氧树脂基体中形成"海-岛"结构。与纯环氧树脂基体相比,当丙烯酸酯质量分数为10%时,经PEA和PBA改性的聚丙烯酸酯/双酚A-MeTHPA体系的拉伸强度分别降低9.51%和4.00%,而拉伸弹性模量分别降低14.81%和9.52%;玻璃化温度变化不大;而冲击强度分别增加了26.5%和31.0%,断裂延伸率分别增加22.03%和30.07%,增韧效果明显。     

氟代聚丙烯酸酯的合成与膜形貌及疏水性能

在过氧化苯甲酰作用下,利用甲基丙烯酸十二氟庚酯与丙烯酸丁酯、甲基丙烯酸二甲氨乙酯、丙烯酸羟丙酯的溶液聚合反应合成了一种氟代聚丙烯酸酯(FBDH),用场发射扫描电镜(FESEM)、原子力显微镜(AFM)等对其结构、成膜性及膜形貌进行了研究.结果表明,在观察尺寸为50 nm、扫描范围为5 μm×5μm条件下,观察所合成的F...     

Hybrid, elastomeric hydrogels crosslinked by multifunctional block copolymer micelles

Amphiphlic block copolymers consisting of hydrophilic, poly(acrylic acid) randomly decorated with acrylate groups and hydrophobic, rubbery poly(n-butyl acrylate) self-assembled into well-defined micelles with an average diameter of ~21 nm. Radical polymerization of acrylamide in the presence of the crosslinkable micelles gave rise to hybrid, elastomeric hydrogels whose mechancial properties can be readily tuned by varying the BCM concentration.     

Volumetric Properties of 1,1-Dimethylethyl Methyl Ether with Ethyl Acrylate, Butyl Acrylate, Methyl Methacrylate, and Styrene at 298.15 K

Densities of the binary systems of 1,1-dimethylethyl methyl ether (MTBE) with ethyl acrylate, butyl acrylate, methyl methacrylate, and styrene have been measured as a function of the composition, at 298.15 K and atmospheric pressure, using an Anton Paar DMA 5000 oscillating U-tube densimeter. The calculated excess volumes were correlated with the Redlich–Kister equation and with a series of Legendre polynomials. The excess volumes are negative for all the systems studied.     

Novel use of polymer brushes in colloidal lithography to overcome lateral capillary force

A general method has been developed for transferring interfacially trapped, submonolayer hexagonal arrays of silica particles for nano- and mesoscopic surface patterning. Poly(n-butyl acrylate) and poly(n-butyl acrylate-random-N,N-diethylaminoethyl acrylate) brushes were grafted on the substrates via the "graft-from" method using atom transfer radical polymerization. The polymer brush served as an adhesive promoter between the particles and the substrate and proved to be effective for locking the particles in the hexagonal lattice against the lateral capillary force arising from a thin layer of water attached to the surface of the substrate. Several parameters that influence preservation of the order of the particle arrays were examined. These include brush thickness, brush composition, interparticle distance, and particle diameter.     

Volumetric,Viscometric, Ultrasonic,and Refractive Index Properties of Liquid Mixtures of Benzene with Industrially Important Monomers at Different Temperatures

The densities, ρ, viscosities, η, ultrasonic speeds, u, and refractive indices, n _D, of pure benzene, methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), styrene (STY), and their binary liquid mixtures have been measured over the entire composition range at 298.15 K, 303.15 K, 308.15 K, and 313.15 K. The experimental data have been used to calculate excess molar volumes. Partial molar volumes of MA/EA/BA/STY in benzene at infinite dilution and at different temperatures have also been evaluated. The results were discussed in terms of molecular interactions prevailing in the mixtures.     

超低温用紫外光快速固化丙烯酸酯树脂体系的制备及性能

在丙烯酸酯体系中加入填料酚酞基聚芳醚酮（PEKC）,通过紫外光（UV）固化交联制备出可快速固化且耐超低温（液氮）的PEKC/丙烯酸酯体系,通过考察PEKC/丙烯酸酯体系的凝胶率及固化收缩率,确定了其在UV固化下的交联程度及固化收缩状况;通过动态热机械分析表征了PEKC/丙烯酸酯体系的线性热膨胀系数（α）,研究了其在温度变化下的尺寸稳定性;测试并比较了PEKC/丙烯酸酯体系在超低温及室温下的剪切强度,表征了其耐超低温性能。结果表明,PEKC与丙烯酸酯质量比为0~4%的PEKC/丙烯酸酯体系可以实现快速固化,固化5 s后树脂的凝胶率可达80%以上。随着PEKC/丙烯酸酯中PEKC质量比从0增加到4%,固化后PEKC/丙烯酸酯体系在-150~50℃温度范围的线性热膨胀系数由6.71×10^-5℃^-1降低至5.29×10^-5℃^-1,体收缩率由25.61%降低至6.24%,线收缩率由1.78%降低至0.41%,而其断裂延伸率逐渐提高,韧性增强。研究发现,PEKC/丙烯酸酯复配体系的室温拉伸强度都在20 MPa以上,PEKC与丙烯酸酯质量比为3%的PEKC/丙烯酸酯体系铝-玻璃搭接在室温和液氮温度下的拉伸剪切强度分别可达17.48 MPa和17.23 MPa。     

The degradation in tensile strength of polymer-coated glass optical fibres under γ-irradiation

The tensile strength of glass optical fibres when coated with various polymers has been measured as a function of -ray dose. Fibres protected with acrylate, silicone + acrylate or polyimide coatings showed little degradation after receiving a total dose of 1 MGy (they retained >95% of their preirradiated strength). For a fibre with an extruded nylon overcoat the nylon became very brittle after 0.5 MGy, but as far as could be assessed, the strength of the central glass fibre was little affected. Two other types of fibre, both protected with fluorinated polymers, were severely weakened after 0.1 MGy (their tensile strength being reduced to < 40% of their pre-irradiated strength). Experimental results are given supporting the hypothesis that the degradation results from gaseous fluorine-containing species chemically attacking the surface of the glass fibre.