High Oil-absorptive Composites Prepared from Non-woven Fiber and Sponges with 4-tert- butylstyrene-EPDM-divinylbenzene Graft Polymer

4-tert-butylstyrene-EPDM-divinylbenzene graft terpolym-er (PBED) was prepared by graft cross-polymerization in toluene using BPO as an initiator. The gel-PBED and sol-PBED were isolated from extraction of tetrahydrofuran (THF), and then they were identified by IR spectr-oscopy. The maximum oil-absorptivity of gel-PBED produced from the optimum reaction conditions was 8420% but its swelling rate was very low. The highest oil-absorptivity of photocrosslinked sol-PBED film was 5 800%. Although its oil absorbency was not as high as gel-PBED' s, swelling rate was higher than that of gel-PBED and was suitable for commercial purpose. After swelling in oil, neither gel-PBED nor photocrosslinked sol-PBED film having high oil-absorptivity had sufficient mechanical strength to be taken out of oil wholly. As is known, composite technique is one of the useful methods for reinforcing them. Fibers, sponges and non-woven cloths were used as reinforcers or supporters in this work. Oil-absorptivities and swelling kinetics     

引发剂对硅烷化杨木单板/聚乙烯薄膜 复合材料性能的影响

为分析引发剂对硅烷偶联剂的协同效应,以高密度聚乙烯(HDPE)薄膜为胶黏剂,乙烯基三甲氧基硅烷(A-171)和引发剂过氧化二异丙苯(DCP)为杨木单板的改性剂,制备硅烷化杨木单板/HDPE薄膜复合材料。分别采用力学试验机、动态力学分析仪(DMA)和冷场发射扫描电子显微镜分析引发剂DCP用量(0、0.05%、0.10%、0.15%)对复合材料物理力学性能的影响。结果表明:在引发剂DCP的诱导下,硅烷化杨木单板与HDPE薄膜发生了化学交联反应,形成了优良的胶接结构,硅烷化杨木单板/HDPE薄膜复合材料的力学性能、耐水性能和耐高温破坏性能都显著增强。当引发剂DCP添加量达到0.15%时,复合材料的胶合强度、木破率、静曲强度和弹性模量值分别由1.02 MPa、2%、60.10 MPa、5 102 MPa增加至2.07 MPa、95%、77.20 MPa、6 822 MPa; 吸水率和吸水厚度膨胀率分别由77.80%和5.79%降低至53.75%和4.09%。DMA结果显示,复合材料的耐高温破坏能力随DCP添加量的增加而改善,当DCP用量由0增至0.15%时,复合材料在130 ℃时的储能模量保留率由44.19%提高到88.34%,胶接界面层失效的温度点从147 ℃提高至197 ℃。     

Longitudinal Mechanical Properties of Small-Diameter Polyurethane Vascular Graft Reinforced by Tubular Knitted Fabric

The vascular graft with 4 mm diameter was prepared by casting one layer of polyurethane (PU) film onto the knitting tubular fabric as the reinforced support. The effects of different PU content and wall thickness on the longitudinal mechanical properties of vascular graft were investigated. The breaking elongation, breaking force, initial modulus and breaking work were studied. The results showed that the longitudinal mechanical properties of vascular graft were enhanced as the content of polyurethane increased, which resulted from the combination of PU excellent elasticity and fabric preferable strength.     

Preparation and characterization of chitosan/carboxymethylated konjac glucomannan blend films

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2% (weight) chitosan acetic acid solution with 1.5% (weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30% (weight). The CS/ CMKGM blend films provided promising biomedical applications. Foundation item: Supported by the National Science Foundation of China (No.29977014). Biography: Zheng hua (1965-), male, Associate professor, research direction: renewable resource chemistry.     

环氧大豆油/环氧树脂丙烯酸酯的合成及其性能研究

以可再生资源的大豆油衍生物环氧大豆油(ESO)为基体,可以制备环氧大豆油丙烯酸酯(AESO),但该低聚物所成UV固化膜附着力不佳,力学性能较差.文中利用环氧树脂优良的粘接性能和力学性能来改善纯环氧大豆油丙烯酸酯固化膜的这些不足.首先将环氧大豆油和环氧树脂混合,利用丙烯酸对环氧基接枝制备了环氧大豆油/环氧树脂丙烯酸酯(AESO-EA)低聚物,进一步在光引发剂Doracur1173的引发下共聚得到环氧大豆油丙烯酸酯/环氧树脂丙烯酸酯UV固化膜.通过拉伸性能测试、铅笔硬度测试、附着力和冲击性能的测试对固化膜进行了性能分析.测试结果表明,引入了环氧树脂后的固化膜性能显著提高.通过比较分析,当环氧树脂E-44的添加量为环氧大豆油质量的6%左右时,UV固化膜整体性能最佳.     

The effect of water content in crude oil on the tribological behavior of screw pump’s stator rubber

It is worthy of studying the effect of water content in crude oil on tribological behavior of stator rubber, because the different water content would affect the swelling and wear of rubber. Compatibility of dewatered crude oil and water was observed after mixture of dewatered crude oil and water （called oilwater mixture） was mechanical stirred and statically placed. Static etching experiment of samples in oil-water mixture was performed using hanging patch test. Wetting contact angle of oil- water mixture on rubber surface was measured by contact angle meter. Tribological behavior of samples in mixture was measured using a ringonblock tester. The result shows that when the water content is less than 15 %, water can blend with dewatered crude oil, and oil-water separation happens when water content was more than 15 %. With the increasing of water content in crude oil, Wettability of mixture and swelling increment of samples decrease. The wear loss of sample increases after treated by swelling experiment, and FKM owns better wear resistance than NBR.     

静态破碎剂的轴向膨胀力学性能实验研究

针对静态破碎剂轴向膨胀力学行为进行了深入研究,提出了测量静态破碎剂膨胀压的轴向输出法,设计了测试系统及核心钢筒组件.分别采用轴向输出法和外管法对静态破碎剂膨胀压进行了测试.通过对比在不同孔径条件下两种方法测得的膨胀压,分析了孔径大小对静态破碎剂轴向膨胀压及其输出率的影响.结果表明:轴向输出法能够可靠准确测得静态破碎剂膨胀压;在固定的高径比条件下,静态破碎剂轴向膨胀压随孔径尺寸增大而增加;孔径小于50 mm时,自封孔效应导致静态破碎剂输出轴向膨胀压的能力减弱;孔径大于150 mm时,轴向膨胀压与径向膨胀压趋于一致,轴压输出率达100%.     

车用二甲醚橡胶密封件相容性

针对二甲醚(DME)发动机动密封部位必须采用的弹性密封材料,深入展开了车用DME与橡胶密封材料的相容性研究.试验测试了不同橡胶材料耐受DME介质的能力,比较分析了各类材料在DME中浸泡72 h前后的体积与质量变化率,并对比了浸泡前后的拉伸强度、撕裂强度、硬度等力学性能.结果表明:三元乙丙橡胶(EPDM)具有相对良好的耐受DME的能力;车用DME中杂质含量、润滑添加剂成分及比例、EPDM材料组分对EPDM耐受DME性能存在一定影响;当DME发动机燃油系统标定采用车用柴油标定时,EPDM短期内耐车用柴油能力处于可接受的范围.     

Swelling Studies of Chitosan-Gelatin Films Cross-Linked by Sulfate

0　IntroductionChitosanisadeacetylatedderivativeofchitin ,containinginitsstructure glucosamineandacetylglucosamine joinedthroughβ (1→ 4 )linkages.ItisinsolubleinwaterandcommonorganicsolventsbutsolubleatapHunder 6 .5acidicmedia.Duetoitsexcellentbiodegradableandbiocompatiblecharacter,chi tosanhasbeenexaminedextensivelyinthepharmaceuticalindus tryforitspotentialinthedevelopmentofdrugdeliverysys tems[1 ,2 ] .Gelatinisabiodegradablepolymerofwidesafety ,pro ducedfromcollagen ,themostabundantprote…     

甲基丙烯酸甲酯在流延聚丙烯薄膜表面的紫外光引发接枝改性

通过紫外光引发在流延聚丙烯(CPP)薄膜表面接枝甲基丙烯酸甲酯(MMA),考察以二苯甲酮(BP)和二氟二苯甲酮(DFBP)分别作为光引发剂时MMA的接枝效果。以傅里叶红外光谱分析薄膜表面物质的结构,润湿角测量仪表征薄膜的表面亲水性。结果表明:以BP作为光敏剂时MMA的接枝率可达0.032 06%;接枝后在1 734 cm-1处薄膜表面产生羰基吸收峰;水在CPP薄膜表面的接触角随着接枝率的增加而降低,表明MMA在CPP表面接枝可以改善薄膜的表面亲水性。     

多功能全物理交联水凝胶的制备及性质

以丙烯酸羟乙酯、 ι-卡拉胶、 聚乙烯醇和氯化钙为原料, 采用自由基聚合和冻融循环两步法制备水凝胶, 并对水凝胶的机械性能、 自恢复性能、 溶胀性能、自愈合、抗疲劳性能和导电性进行测试和分析. 结果表明： 水凝胶具有较高的机械强度, 其断裂应力为625.77 kPa, 断裂伸长率为604.48%;  水凝胶溶胀率较低, 且具有优异的自恢复性、 抗疲劳性和导电性.      

光固化有机-无机杂化膜性能及其微观形貌

用环戊二烯对亚麻籽油进行改性,合成了改性亚麻籽油（MLO）低聚物。用丙基硫醇三甲氧基硅烷(MPTS)通过溶胶-凝胶法制备了新型的多功能巯基硅氧烷溶胶(MPTS溶胶)。把巯基硅氧烷溶胶、光引发剂加入到MLO低聚物中,制备了紫外光固化有机/无机混杂膜。用热失重分析(TGA)评价了MPTS溶胶对混杂膜热稳定性的影响,用原子力显微镜（AFM)对MPTS/MLO混杂膜的显微形貌进行了观察分析,用Photo DSC对混杂膜的光固化反应性进行了测试。结果表明: 混杂膜的热稳定性比纯MLO膜高,混杂膜具有微相分离结构, 巯基硅氧烷溶胶能够提高MLO体系自由基聚合速率。     

有机硅聚合物共混改性环氧树脂水分散液的制备、表征及成膜后的性能

用氨基硅油微乳液与水的原位分散方法,制备了有机硅聚合物共混改性接枝环氧树脂水分散液,采用FT—IR、ATR、TEM以及TGA等对该水分散液的粒子形态、粒径以及成膜后的物理性能进行了表征。实验结果表明：与未改性的水分散液相比,改性水分散液的粒径减小,粒径分布变宽,粘度增大。TEM照片表明：有机硅聚合物在分散过程中被包裹在环氧树脂内部,形成“核-壳”结构的复合颗粒。改性水分散液成膜后的疏水、疏油性能和热性能显著提高,表面能降低。膜的超薄切片TEM照片显示：有机硅聚合物在成膜过程中向表面取向与迁移,FT—IR与ATR的测试结果进一步证实它们在膜的表面富集。     

高强度物理-化学混杂双网络水凝胶的制备及性质

以聚乙烯醇（polyvinyl alcohol, PVA）和丙烯酰胺（acrylamide, AM）为原料, 采用“一锅煮”及紫外辐照结合冷冻 解冻两步聚合法制备聚乙烯醇/聚丙烯酰胺(PVA/PAM)混杂双网络水凝胶, 并对水凝胶的力学性能、 溶胀性能、 失水性能以及自愈合性进行测试和分析. 结果表明, PVA/PAM混杂双网络水凝胶具有较高的力学强度, 其拉伸强度为428 kPa, 失水速率和单网络水凝胶相比较慢, 具有一定的自愈合性.     

二甲基二氯硅烷改性接枝环氧树脂的合成研究

环氧树脂与甲基丙烯酸、甲基丙烯酸甲酯以及苯乙烯接枝共聚,合成了接枝环氧树脂水分散体,采用二甲基二氯硅烷（DMS）来改性接枝环氧树脂分散体,通过对乳液的粒径分析以及对聚合产物的结构表征,并考察了乳液及涂膜性能的影响。研究表明,有机硅的引入影响接枝环氧水分散体的粒径分布,提高了固化涂膜的热分解温度,提高了固化涂膜的耐水性、粘结性和机械性能。     

聚乙烯预辐射接枝丙烯酸研究

采用预辐射法研究了丙烯酸对聚乙烯膜的接枝反应。结果表明,在真空环境下添加阻聚刑铁盐可使接枝反应顺利进行,加入无机酸可促进接枝反应。还研究了单体浓度、辐照剂量和贮存时间的影响,测定了接枝膜的吸水率、吸碱率和机械性能。     

含有生物质纤维的聚酰亚胺薄膜的制备及性能测试

聚酰亚胺(polyimides,PI)是以二酐或二胺合成的耐高温聚合物,因其耐高温性能强成为使用温度最高的工业化聚合物材料之一。针对目前PI薄膜在强度方面存在的断裂延伸率低、拉伸强度低等问题,通过调节聚合物的质量浓度、比例、加料方式、加入生物质纤维等方式制得了不同强度的聚酰亚胺薄膜。以4,4-二氨基二苯醚和3,3,4,4-联苯四甲酸二酐作为反应的前驱体,在交联剂的存在下,采用正加料法制备聚酰胺酸(polymer polyacrylic acid, PAA),将制备好的PAA放置在表面铺有均匀藕丝的培养皿中,加热使其亚胺化,制得聚酰亚胺薄膜。结果表明含有藕丝的聚酰亚胺薄膜的断后标距和弹性模量均低于未掺杂藕丝的薄膜,其中PI-2%藕丝断裂延伸率为6.49%,抗拉强度达67.33 MPa,最大力数据为57.47 N,远高于未掺杂藕丝薄膜力学数据。研究表明藕丝纤维的加入在一定程度上增强了薄膜的力学性能。     

PDMAA/Clay纳米复合水凝胶的制备与性能

以无机黏土为交联剂,采用偶氮二异丁腈(AIBN)为引发剂制备了新型的聚N,N ＇-二甲基丙烯酰胺/黏土(PDMAA/Clay)纳米复合水凝胶,作为对比,采用过硫酸钾(KPS)为引发剂制备了相对应的水凝胶.对两种纳米复合水凝胶的结构、形态、溶胀行为和力学性能等进行了研究.试验表明,黏土的结晶结构均已被破坏,黏土规整的片层被剥离并在凝胶中无序分布,起到交联剂的作用.随着黏土含量的增加,水凝胶的溶胀速率和溶胀度降低.采用AIBN制备的PDMAA/Clay水凝胶具有更好的韧性及更高的断裂强度,其断裂伸长率可达1 800％以上,而KPS制备的水凝胶的断裂伸长率在1 200％左右.     

喷油器柱塞副动态泄漏及特性

为了研究高压共轨喷油器柱塞副的动态泄漏特性,建立了柱塞副间隙燃油流动的数学模型,通过有限差分法对数学模型进行数值计算,研究了不同轨压下柱塞副燃油的平均动态泄漏率的变化趋势,与试验值进行对比,验证该数学模型的有效性,并分析了轨压、进口燃油温度、柱塞最大升程和喷射脉宽四种因素对柱塞副动态泄漏量的影响及在不同柱塞速度下,油膜压力、厚度和温度参数的变化趋势。结果表明,在一个喷油循环内,动态泄漏率的变化曲线与控制腔油压变化曲线相似,平均动态泄漏率随着喷油器的轨压、入口燃油温度和柱塞最大升程的增加而增加,但随着喷射脉宽的增加而减小;随着柱塞速度由正速度到负速度的过程,油膜的厚度逐渐变薄,油膜的温度整体上升,油膜的压力变小。     

乳状液膜脱酚的进一步研究

对生产古马隆树脂的含酚废水采用乳状液膜法脱酚进行了探讨 ,分析了乳状液膜的稳定性和搅拌强度 ,内相试剂的浓度、油内比、乳水接触时间、温度、酸度及不同表面活性剂浓度对除酚效率的影响 .对酚质量分数为 0 0 6 %的废水 ,经一级处理可净化到 0 0 0 0 5 %以下 ,净化率达 99%以上 .讨论了表面活性剂的适宜用量及液膜的循环利用