叶面亲和型阿维菌素微胶囊的制备及pH响应性释放性能

为减少农药流失，设计了一种叶面亲和型缓释微胶囊。以甲基丙烯酸甲酯（MMA）接枝改性羧甲基纤维素（CMC）得到羧甲基纤维素-聚甲基丙烯酸甲酯（CMC-g-PMMA），然后利用自组装负载阿维菌素（AVM）形成载药微胶囊（CMC-g-PMMA@AVM），通过多巴胺（DA）包覆提高CMC-g-PMMA@AVM的叶面亲和性。采用扫描电镜、红外光谱、热重分析等对其结构和形貌进行表征，研究了微胶囊的载药性能、叶面亲和性及响应释放性能。结果显示，DA/CMC-g-PMMA@AVM为平均粒径126nm的球形粒子，多巴胺的包覆可有效提高微胶囊的载药性能，包封率可达88.56%；增强AVM的叶面亲和性，使其叶面滞留量相对于阿维菌素水乳液提升30.56%；赋予AVM优异的抗紫外光分解性能，强紫外光照射60min后，由AVM水乳液中AVM的残留率14.03%提高到DA/CMC-g-PMMA@AVM中的59.55%。载药微胶囊中药物释放具有pH响应，在pH=5条件下出现爆释，药物释放过程符合Weibull模型，受Fick扩散控制。     

PMA表面接枝包覆纳米TiO2及其在PP中抗紫外老化的研究

以硅烷偶联剂对纳米TiO2进行表面预处理，在此基础上以聚甲基丙烯酸（PMA）对其表面接枝包覆，后以马来酸酐接枝聚丙烯（PP-g-MAH）为载体，通过母料复合工艺制备了PP纳米复合材料。分析了处理后纳米TiO2的结构并对其在PP中的分散情况及抗紫外老化性能进行了比较。结果表明：PMA在纳米TiO2表面接枝率约为50％；与未处理TiO2及硅烷处理样品相比，PMA接枝包覆使纳米TiO2在PP中的分散均匀性及抗紫外老化性能均获得了改进。     

PMMA接枝纳米ZnO复合粒子改性PVC塑料性能研究

通过原位聚合将甲基丙烯酸甲酯（MMA）接枝于纳米ZnO表面,制备了PMMA接枝纳米ZnO复合粒子,将其加入聚氯乙烯（PVC） 基体中进行改性。研究了纳米ZnO粒子在PVC基体中的分散性和PVC复合材料的力学性能,探讨了改性纳米ZnO粒子填充PVC材料的抗紫外线性能。结果表明,改性后的纳米ZnO粒子在PVC基体中分散均匀, 提高了纳米ZnO粒子与PVC基体之间的相容性,使改性PVC材料的拉伸强度达到78 MPa,比纯纳米ZnO粒子改性PVC提高了35 %;冲击强度提高了近1倍,达到13.6 kJ/m2;加入改性纳米ZnO粒子的PVC还具有明显的吸收紫外线功能。     

硅烷偶联剂对纳米Al2O3改性的研究

本工作以改善纳米粒子在环氧树脂基体中的分散性,提高无机粒子与基体的界面结合力为目的,选择了硅烷偶联剂KH550和KH570分别对纳米Al2O3粒予表面进行改性。文章系统研究了各种聚合条件（加料顺序、偶联剂加入量、反应时间）对改性效果的影响。TGA测试表明获得了不同接枝率的改性粒子。改性粒子与环氧树脂反应后进行的TGA测试以及FTIR测试证明了KH550改性的纳米粒子能够与环氧树脂发生反应,而KH570改性的纳米粒子不能发生反应。     

油酸对壳聚糖/玉米醇溶蛋白复合膜液流变及膜性能的影响

为了提高壳聚糖/玉米醇溶蛋白膜的机械性能，将壳聚糖液与玉米醇溶蛋白液共混，向其中加入0%、15%、30%、45%（w/w）的油酸改性，研究膜液的粒径、zeta电位、静态和动态流变特性；然后，分析油酸添加量对膜阻隔性能，机械性能和相容性的影响。结果表明：添加油酸后，膜液体系粒径增大、分散均匀，添加30%油酸的膜液分散性更好，PDI为0.34，粒径为1307.5nm。随着油酸含量增大，膜液粘度减小，流动指数增大，弹性模量和粘性模量增加。OA-30膜机械性能较好，抗拉强度达到36.37MPa，断裂延伸率达到22.32%。膜的阻隔性增强，水蒸气、氧气透过率分别降低了44.21%和66.52%。复合膜中壳聚糖与玉米醇溶蛋白分子相容性好，表面光滑平整。综上所述，油酸改性改善了壳聚糖/玉米醇溶蛋白复合膜性能。     

聚甲基丙烯酸甲酯／纳米SiO2复合粒子的制备与表征

采用甲基丙烯酸-3-甲氧基硅丙酯（MPs）对分散于甲基丙烯酸甲酯（MMA）中的纳米SiO2粒子进行偶联改性，得到了表面改性的纳米SiO2单体分散液，用原位悬浮聚合方法制备了不同SiO2含量的PMMA／纳米SiO2复合粒子。通过红外光谱、透射电镜、差示扫描量热分析和热重分析等方法对制备的纳米复合粒子进行了表征，结果表明，纳米SiO2粒子在PMMA中分散良好；MMA可通过与MPS的共聚而有效地接枝到SiO2粒子表面，当SiO2含量为6．6％（质量分数，下同）、MPS用量为0．06g／gSiO2时，其接枝率可达73．8％；同时，纳米SiO2的引入可提高PMMA的耐热性能，当Si02含量为14.7％时，其玻璃化转变温度和最大热分解速率时的温度分别提高了11．8℃和18．8℃。     

硅烷化聚琥珀酰亚胺负载阿维菌素的制备与性能

为了减少农药的流失和降解,采用纳米材料与技术开发新型纳米剂型具有巨大潜力。本文以3-氨丙基三乙氧基硅烷（APTES）和丁二胺（DBA）为改性单体,采用胺解开环反应制备了硅烷化聚琥珀酰亚胺（PDSi）,并通过自组装方式负载阿维菌素（AVM）得到AVM@PDSi纳米体系。结果表明,相较于原药,AVM@PDSi对叶面的黏附性明显提升,叶面滞留量提高了56.50%。PDSi材料具有良好的抗氧化活性,PDSi对1,1-二苯基-2-苦基肼（DPPH）自由基的清除率最高可达41.88%。AVM@PDSi具有良好的抗紫外性能,在相同的紫外强度照射下（E_max=365nm）,AVM@PDSi半衰期比原药AVM延长了近一半。AVM@PDSi具有良好的缓释性能和pH响应释放性能,在pH=9时释放最快;在pH=7时,AVM@PDSi-3在72h后累积释放量为67%。研究表明,AVM@PDSi具有良好的储存稳定性,并且保留了AVM的杀虫活性。     

苯乙烯无皂乳液聚合接枝纳米TiO2的研究

采用无皂乳液聚合法，使苯乙烯单体（St）在烷基化预处理的纳米TiO2粒子的表面进行接枝聚合，得到了稳定的以纳米TiO2粒子为核、接枝聚苯乙烯为壳的复合颗粒（TiO2-g-PS）。研究了烷基化预处理以及聚合条件（单体浓度、引发剂浓度、反应时间）对TiO2表面接枝改性的影响，并对其聚合机理进行了探讨。结果表明：PS以化学键成功地接到纳米TiO2的表面，并且可以通过改变接枝聚合的条件来调节粒子上所接聚苯乙烯的结构，为进一步优化纳米粒子填充聚合物复合材料的结构和性能之间的关系建立基础。     

羧甲基壳聚糖-蓖麻油基聚氨酯农药缓释微球的制备及性能

以羧甲基壳聚糖（CMCS）、蓖麻油（CO）和异佛尔酮二异氰酸酯（IPDI）为原料，自乳化法制备了羧甲基壳聚糖-蓖麻油基聚氨酯微球（CO-CMCS-PU），通过分子自组装法负载阿维菌素（AVM）得到载药微球（CO-CMCS-PU@AVM）。采用FTIR、1HNMR、SEM、TGA等对产品结构及形貌进行表征，并探究了不同药量载药微球的包封率、缓释性能、抗紫外性能、叶面接触角和黏附性能。结果表明，相比AVM分散液，紫外照射后载药微球中AVM的保留率提高到43%，说明CO-CMCS-PU载体的抗紫外性能良好；载药微球比AVM分散液在黄瓜叶面上的接触角降低了20%以上，滞留量提高了40%以上，说明其在叶面上有较好的黏附性和润湿性；载药微球包封率可达80%以上，具有良好的缓释和pH响应释放性能，释药行为符合First-order动力学模型，药物释放受Fickian扩散控制。     

玉米醇溶蛋白体内外降解行为的研究

目的：考查玉米醇溶蛋白体内外降解的情况。方法：用95％的乙醇溶液配制65％（g／mL）醇溶蛋白胶体溶液,用压模成型方法制备玉米醇溶蛋白棒,通过特性粘度、质量变化、扫描电镜观察等研究醇溶蛋白体内外降解过程。结果：醇溶蛋白体内外均能降解,在体内外降解的玉米醇溶蛋白棒只是表面变粗糙,但总体形态没有变化,且体内降解率大于体外降解率。随着降解的进行,棒表面逐渐粗糙,在体内还出现了凹状吸收。     

不同紫外波长对热塑性淀粉塑料表面的光交联改性研究

为有效提高热塑性淀粉塑料（TPS）的力学和耐水性能，本文提出用不同波长的紫外光照的方法来实现TPS表面的光交联改性。将光引发剂2,4,6?三甲基苯甲酰基二苯基氧化膦（TPO）的乙醇溶液涂覆于TPS表面后进行紫外光照射，研究了不同紫外光波长（254、308、365 nm）对TPS交联度、力学性能、动态力学性能、耐水性和吸湿性的影响。结果表明，与254 nm和365 nm紫外光照后的样品相比，308 nm光照后TPS样品的拉伸、弯曲和冲击强度最大，分别为4.1 MPa，2.7 MPa和96.8 kJ/m²;TPS中淀粉富集区的玻璃化转变温度（T_α）、甘油富集区的玻璃化转变温度（T_β）分别达最高为-37.48 ℃和50.32 ℃，表面接触角最大为75 °，吸水性能也得到显著改善，交联度结果证实此时形成了最佳的交联结构。     

氟硅改性无溶剂环氧涂料的制备与性能

采用甲基丙烯酸十三氟辛酯（TFM）改性氨基硅油（AS）制备氟化氨基硅油（FAS）,并用其改性环氧树脂（EP）探究氨基硅油及氟化氨基硅油添加量对环氧涂层性能的影响。本文通过红外光谱对改性结果进行表征,通过柔韧性测试、画圈附着力测试、铅笔硬度测试、耐冲击测试、热失重测试、接触角测试、紫外加速老化实验和Tafel极化曲线测试,分别评价涂层的柔韧性、附着力、硬度、耐冲击性、耐热性、疏水性、耐候性和防腐性能,通过扫描电镜对涂层断面进行分析,并通过EDS对涂层进行表面元素分析。结果表明,氟添加量为15%制备氟化氨基硅油改性环氧树脂时,氟硅改性EP涂层相对于未改性EP涂层,硬度由2H提升至3H,附着力由2级提升至1级,柔韧性由1mm提升至0.5mm,耐冲击由45cm提升至50cm,热稳定性增强,接触角由70.5°提升至123°,耐紫外老化（432h）由3级提升至1级,E_corr由-0.6187V正移至-0.1720V,I_corr由1.9858×10^-8A/cm²减小至3.7125×10^-10A/cm²。适量氟化氨基硅油的引入,显著提升了环氧涂层的机械性能、耐候性能和防腐性能。     

丙烯酰胺接枝海藻酸纤维的耐碱性研究

采用等离子体处理接枝共聚的方法对海藻酸纤维表面接枝丙烯酰胺,以改善纤维的耐碱性,利用红外吸收光谱和扫描电镜对改性纤维进行表征;探讨了等离子体处理纤维的工艺条件,研究了改性纤维的吸湿性和力学性能。结果表明:海藻酸纤维表面已接枝上丙烯酰胺;等离子体处理和接枝反应最佳工艺条件为:放电功率100 W,放电时间4 min,丙烯酰胺质量分数40%,接枝时间60 min。改性后的纤维碱溶解率为0.23%,吸湿性没有显著变化,但断裂强度提高。     

Superhydrophobic modification of ceramic membranes for vacuum membrane distillation

The hydrophobically modified ceramic membranes have great potential for energy-efficient membrane distillation.In this work,flat-sheet ceramic membranes with a superhydrophobic surface were fabricated by grafting 1H,1H,2H,2H-perfluorooctyltrichlorosilane or 1H,1H,2H,2H-perfluorodecyltriethoxysilane and followed by ultraviolet irradiation.The surface water contact angle was improved from 46° of original ceramic membrane to 159°,which exhibited a stable and excellent superhydrophobic effect.The modified membranes showed a high flux of 27.28 kg· m-2.h-1 and simultaneously maintained an excellent retention rate of 99.99％,when used in vacuum membrane distillation process for treatment ofa 1 wt％ NaCl (75 °℃) aqueous solution.These results suggested that superhydrophobic modification of ceramic surface is a facile and cost-effective way to achieve higher membrane distillation performance.The superhydrophobically-modified ceramic membrane with an excellent desalination capacity would show considerable potential in practical membrane distillation utilizations.     

Mechanical and aging resistance performance of acrylic sheets containing EPDM-graft-poly(styrene-co-methyl methacrylate)

The addition of ethylene-propylene-diene rubber (EPDM) into acrylic sheets was expected to enhance their thermal and UV aging resistance for outdoor applications. According to the dissimilar polarity of EPDM and styrene (ST)/methyl methacrylate (MMA) monomer mixture (20/80% (w/w)) used for preparation of acrylic sheets, this research aimed to modify EPDM via graft copolymerization with ST and MMA to increase its compatibility. The graft copolymerization of ST and MMA at a ST/MMA ratio of 25/75% (w/w) onto EPDM was carried out in the solution polymerization initiated by benzoyl peroxide at 90 °C for 16 h, resulting in 88.1% grafting efficiency. The addition of 1.0–3.0% (w/w) of graft EPDM (GEPDM) into the acrylic sheets increased their impact strength (~ 17–22%), but decreased their flexural strength (~ 12–36%). However, their mechanical properties were improved after thermal and UV aging. Scanning electron microscopy (SEM) based analysis of the modified acrylic sheets revealed that the fracture surface shifted from brittle to ductile failure characteristics after modification. The thermogravimetric analysis results also exhibited that the addition of GEPDM improved the thermal and UV resistance of the modified acrylic sheets by increasing their initial decomposition temperature and activation energy of thermal decomposition.     

Characterization of Surface Modification of Polyethersulfone Membrane

Surface modification of polyethersulfone (PES) membrane surfaces using UV/ozone pretreatment with subsequent grafting and interfacial polymerization on membrane surface was investigated in order to improve the resistance of membrane surface to protein adsorption. The surface modifications were evaluated in terms of hydrophilicity, chemical composition of the surface and static protein adsorption. In both methods, poly(vinyl alcohol) (PVA), poly(ethylene glycol) (PEG) and chitosan were chosen as hydrophilic polymers to chemically modify the commercial virgin PES membrane to render it more hydrophilic as these materials have excellent hydrophilic property. Modified PES membranes were characterized by contact angle and XPS. Contact angles of modified PES membranes were reduced by 19 to 58% of that of the virgin PES membrane. PES membrane modified with PEG shows higher wettability than other hydrophilic materials with the highest contact angle reduction shown for UV/ozone pretreated, PEG grafted PES membrane surface. In general, XPS spectra supported that the PES membranes were successfully modified by both grafting with UV/ozone pretreatment and interfacial polymerization methods. The results of the static protein adsorption experiments showed all surface modifications led to reduction in protein adsorption on PES membranes; the highest protein adsorption reduction occurred with membrane modified by UV/ozone pretreatment followed by PES grafting, which corresponded to the highest contact angle reduction. However, there seems to be no clear correlation between contact angle reduction and reduction in protein adsorption in the case that involved chitosan. Nevertheless, membranes modified with chitosan do show higher reduction in protein adsorption than membranes modified with other materials under the same conditions.     

Grafting of poly(ethylene glycol) monoacrylate onto polycarbonateurethane surfaces by ultraviolet radiation grafting polymerization to control hydrophilicity

In this study, we used a UV radiation grafting method to modify the surface of the biomaterial polycarbonateurethane (PCU). Hydrophilic poly(ethylene glycol) monoacrylate (PEGMA; number‐average molecular weight = 526) as a macromolecular monomer was grafted onto the PCU surface by UV photopolymerization. The Fourier transform infrared and X‐ray photoelectron spectroscopy results of the graft‐modified PCU confirmed poly[poly(ethylene glycol) monoacrylate] block grafting onto the surface. We investigated the effects of the reaction temperature, macromolecular monomer concentration, UV irradiation time, and photoinitiator concentration on the grafting density (GD) in detail. Furthermore, we investigated the effects of GD under various process conditions on the water uptake and water contact angle. The modified materials had a high water uptake and low water contact angle, which indicated that the hydrophilicity of the PCU surface was improved significantly by the introduction of the hydrophilic poly(ethylene glycol) blocks on the surface. The anticoagulant properties of the material might also have been improved. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation and properties of polymerizable silica hybrid nanoparticles with tertiary amine structure

To increase the photopolymerization rate and improve the properties of UV coatings, polymerizable silica hybrid nanoparticles with tertiary amine structure were prepared. Organic compound with isocyanate group was first grafted onto the surface of nanosilica by reaction of nanosilica with isophorone diisocyanate, then the nanosilica bearing isocyanate group reacted with N,N-di(3-propionic acid, 1,4,7-trimethyl-3,6-dioxaoctane-8-yl acrylate, ester) ethanolamine synthesized from tripropylene glycol diacrylate and ethanolamine. The preparation was characterized by ¹H nuclear magnetic resonance (NMR) and Fourier transform infrared spectrometry (FT-IR). Thermogravimetric analysis (TGA) showed that the organic compounds grafted onto the silica decomposed from 256 °C to 650 °C and the grafting percentage based on nanosilica was 105%. The morphology analysis of nanosilica and modified silica by field-emission scanning electron microscopy (FE-SEM) indicated that the silica kept nanosized scale after modification, while the nanosilica dispersion was improved and formation of agglomerates unlikely. Determination of viscosities of coatings with modified nanosilica, it was found that viscosities of the coatings decreased in comparison with the viscosities of coatings with unmodified nanosilica. Compared with pure organic coating, the photopolymerization rate of coatings were faster when modified nanosilica was used from 1 wt% to 5 wt%, but slower when the loadings of modified nanosilica was 7 wt% because co-initiating effects of tertiary amine compound grafted on nanosilica counterbalanced the effects of UV scattering by silica on photopolymerization rate. The hardness and abrasive resistance of cured films also increased and improvement degree was different when the various amounts of modified nanosilica were used.     

本体光交联对热塑性淀粉塑料性能的影响

将光引发剂二苯甲酮直接与淀粉和甘油共混,并通过挤出注塑工艺制备了热塑性淀粉（TPS）塑料,研究了不同紫外光照时长对其力学、动态热力学、热稳定和耐水性能的影响。结果表明,当紫外光照时长为15 min时,TPS可形成最佳的交联网络结构,显著提高其性能,拉伸强度,弯曲强度,冲击强度分别可达4.57 MPa、7.1 MPa及69.39 kJ/m2;储能模量有所提高,玻璃化转变温度达到最高,Tβ和Tα分别为-35.63 ℃和53.96 ℃;最大分解速率对应的峰值温度（Tp）由TPS的317.81 ℃提高到330.48 ℃;表面接触角由纯TPS的42.3 °增加至77.2 °,显著提高了耐水性能。     

改性石墨烯对环氧树脂涂层耐腐蚀性能的影响

将改性后石墨烯粉末通过球磨机均匀分散于环氧树脂涂料中以提高7A52铝合金表面有机涂层的耐腐蚀性能。通过接触角、吸水率、红外光谱、开路电位及交流阻抗测试,分别评价改性石墨烯环氧树脂涂层的表面润湿性、耐水性能、耐蚀性,并通过扫描电子显微镜对石墨烯粉末及环氧树脂涂层断面形貌进行分析。结果表明:环氧树脂涂料中添加0.8%改性石墨烯粉体后,接触角由86.77°增加至101.43°,提高16%,表面由亲水性变为疏水性,涂层的耐水性提高,吸水率降低0.21%。0.8%改性石墨烯涂层在3.5%NaCl溶液中稳定后的开路电位较未添加石墨烯涂层增加0.14 V,阻抗值高出未添加改性石墨烯涂层半个数量级,且电荷转移电阻R_ct比未添加改性石墨烯涂层R_ct高出1.78×10 ⁷ Ω/cm ²,涂层的耐腐蚀性大大提高。红外光谱表明,改性石墨烯并未改变环氧树脂结构,涂层中的改性石墨烯是影响涂层性能发生变化的重要因素。研究表明改性石墨烯的加入可以有效提高涂层的耐蚀性,并且当改性石墨烯添加量为0.8%时,涂层具有优异的耐腐蚀性能。