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1.
采用球磨法制备的纤维素纳米晶(CNC)及市售纳米ZnO对聚乙烯醇(PVA)进行改性,改善了PVA膜的力学性能,并且,赋予其抗菌性,测试复合膜的力学性能、水蒸气透过性能及抗菌性能。结果表明,加入CNC后,提高了PVA膜的力学性能和阻湿性能,加入纳米ZnO后,复合膜对金黄色葡萄球菌具有一定的抗菌性能,并且,能进一步提高复合膜的拉伸强度,但是,降低了复合膜的阻湿性能。当CNC的添加量为3%、纳米ZnO∶CNC=2∶1(摩尔比)时,复合膜综合性能较好,拉伸强度为73.7 MPa,与纯PVA膜相比,提高了77.2%;断裂伸长率为3.8%,与纯PVA膜相比,提高了46.1%;水蒸气透过系数为3.44×10-13 g·cm/(cm2·s·Pa),与纯PVA膜相比,提高了11.7%。  相似文献   

2.
以海藻酸钠为基材,纤维素纳米晶(CNC)为增强增韧剂,以山梨酸钾为防腐保鲜剂,采用流延法制备海藻酸钠/CNC/山梨酸钾复合膜。研究CNC、山梨酸钾的加入对海藻酸钠膜光学性能、力学性能、水蒸气阻隔性能等的影响。结果表明:随着CNC含量的增加,复合膜的透光率先增加后降低;添加山梨酸钾后,复合膜的透光率逐渐下降。CNC的加入使复合膜的拉伸强度和断裂伸长率均先提高后降低,水蒸气阻隔性能先降低后升高。随着山梨酸钾的添加,复合膜的拉伸强度逐渐降低,断裂伸长率先降低后增加,水蒸气阻隔性能先升高后降低。当CNC含量为5%、山梨酸钾含量为3%,复合膜的拉伸强度为120.78 MPa,断裂伸长率为4.38%,水蒸气透过系数为7.62×10-13 g·cm/(cm2·s·Pa),与纯海藻酸钠膜相比,分别提高了21.66%、27.33%和17.59%,复合膜综合性能最佳。  相似文献   

3.
针对低温多效海水淡化过程中金属换热管路的腐蚀问题,采用硅烷(APS)、纳米氧化锆(Zr O2)及纳米氧化铈(Ce O2)在铝合金表面制备硅烷/纳米Zr O2·Ce O2复合膜层,研究其抑制金属腐蚀的效果。结果表明,当纳米Zr O2、纳米Ce O2添加浓度为50 mg/L时,复合膜层的综合性能较好;通过动电位极化法和电化学阻抗法探究了复合膜层在不同温度下的耐蚀性能,结果表明硅烷/纳米Zr O2·Ce O2复合膜层的防护效果较单一硅烷膜层有明显提升。随着溶液温度的升高,硅烷/纳米Zr O2·Ce O2复合膜层的耐蚀性能降低较少,纳米Zr O2、纳米Ce O2的协同作用使得硅烷膜更能适应高温高盐环境。  相似文献   

4.
《塑料科技》2019,(11):6-10
以低密度聚乙烯(LDPE)为基体材料、改性纳米二氧化钛(Ti O2)/山梨酸钾(PST)为复合抗菌剂,通过密炼机和单螺杆吹膜机制备了纳米抗菌LDPE/Ti O2/PST复合膜,并对抗菌薄膜的热性能、红外光谱和抗菌性能进行了研究。结果表明:LDPE/Ti O2/PST复合膜的抗菌性能明显高于纯LDPE膜,且随着复合抗菌剂用量的增加而不断提高。此外,当复合抗菌剂用量为LDPE基体的0.75%时,复合膜的结晶度达到31%,高于纯LDPE膜。  相似文献   

5.
采用溶液流延法以豌豆淀粉(PS)和聚乳酸(PLA)为原料制备了豌豆淀粉/聚乳酸(PS/PLA)双层薄膜。通过对双层薄膜的吸水性、溶解性、水蒸气透过性、拉伸性能、表面形貌等进行测试,研究了薄膜的力学性能、疏水性能以及水蒸气阻隔性能。结果表明:随着双层膜中聚乳酸层的比例增加,双层薄膜的吸水性、溶解性和水蒸气透过性逐渐降低,拉伸强度和拉伸模量逐渐增加,断裂伸长率逐渐下降,表明水蒸气阻隔效果明显,增加了膜的韧性,降低了膜的强度。当PLA和PS的质量比为50:50时,PS/PLA双层膜的拉伸强度为(13.47±0.75)MPa,拉伸模量为(0.848±0.002)GPa;断裂伸长率为(16.11±0.16)%,水蒸气透过系数为0.27×10-10 g·cm/(cm2·s·Pa)。  相似文献   

6.
采用溶胶-凝胶法制备了Ti O2粉体,并以聚乙烯醇和聚多巴胺为载体,采用浇铸法制备出Ti O2光催化薄膜。对膜的耐水性和光催化降解性能进行了测试。结果表明,光照30min甲基橙的降解率为89.33%,光照60min甲基橙的降解率为93%。随着薄膜内Ti O2添加量的增加,膜的光催化性能逐渐增强,在水中的吸水率逐渐降低。  相似文献   

7.
以马铃薯淀粉为基材,壳聚糖和纳米TiO_2为增强相,研究壳聚糖和纳米TiO_2对马铃薯淀粉成膜性能的影响。通过溶液共混法将壳聚糖的乙酸溶液与马铃薯淀粉糊化液,按照4∶6的比例均匀混合,加入纳米Ti O2流延成膜,研究壳聚糖和纳米TiO_2对复合膜的阻氧性及透湿性的影响;用XRD、SEM表征复合膜的结构与形态。研究结果表明,马铃薯淀粉与壳聚糖、纳米TiO2组分成膜时具有良好的相容性;壳聚糖和纳米TiO_2能有效改善复合膜的水蒸气透过性和阻氧性;纳米TiO_2/壳聚糖/马铃薯淀粉复合膜较马铃薯淀粉单膜、马铃薯淀粉/壳聚糖复合膜、马铃薯淀粉/纳米TiO_2复合膜的阻氧性提高了43. 38%、7. 56%、19. 14%;水蒸气透过率降低了32. 41%、39. 18%、30. 89%。壳聚糖和纳米TiO_2添加到马铃薯淀粉液中共混制膜,能够增强复合膜的性能。  相似文献   

8.
通过简单可控的电沉积方法制备了一种高性能MnO2包覆Ti基电催化膜(MnO2/Ti)。系统地表征了所制备的MnO2/Ti膜形貌、元素含量、价态分布和电化学阻抗以及循环伏安交流测试,并考察了流速和电流密度对MnO2/Ti膜水处理性能的影响。结果表明,MnO2均匀分布在Ti膜表面,电沉积MnO2可以显著提高Ti膜电化学活性,增强Ti膜电催化氧化性能,从而提升Ti膜自清洁能力。在电流密度为10 mA/cm2,流速为1.5 mL/min的工作条件下,乳化油的去除率高达91%。此外,MnO2/Ti膜具有良好的稳定性和可重复使用性能。氧化机理表明,MnO2/Ti膜在电催化处理过程中具有直接和间接氧化活性,MnO2涂层可提高Ti膜的直接氧化能力和·OH、O2·-产量。  相似文献   

9.
以微晶纤维素(MCC)和聚乙烯醇(PVA)为原料,1-丁基-3-甲基咪唑氯盐([Bmim]Cl)为溶剂,通过MCC溶解再生与PVA共混制备再生纤维素(RGC)/PVA基膜,并利用壳聚糖(CS)和纳米二氧化钛(TiO2)共混液包覆方法制备RGC/PVA/CS/TiO2抗菌复合膜。通过FT-IR、XRD和SEM对复合膜的形貌和结构进行表征,并对复合膜的热学、力学、光学、阻隔和抑菌等性能进行测试分析。研究结果表明:壳聚糖和二氧化钛成功复合于纤维素基膜,RGC/PVA/CS/TiO2复合膜的热分解主要由CS-TiO2包覆层和RGC/PVA基膜的分解构成。与再生纤维素(RGC)膜相比,当TiO2质量分数为0.2%时,RGC/PVA/CS/TiO2复合膜的拉伸强度提升了39.28%,断裂伸长率提升了51.66%,透光率保持在88.72%,氧气透过率下降了47.77%,且对大肠杆菌、金黄色葡萄球菌和枯草杆菌具有良好的抑制作用。  相似文献   

10.
以氧化石墨烯改性纳米二氧化钛为光催化活性成分,通过流延成型法制备了壳聚糖/纳米纤维素/石墨烯改性纳米TiO2光催化复合膜。利用热重分析仪(TG)、傅里叶红外光谱仪(FTIR)和扫描电子显微镜(SEM)对复合膜的结构进行表征。研究了壳聚糖/纳米纤维素/改性纳米TiO2复合膜的力学性能,对比了复合膜对亚甲基蓝及甲基橙的光催化降解性能。结果表明,改性纳米TiO2的添加提高了壳聚糖复合膜的力学性能及耐热性能。改性纳米TiO2质量分数为4%的复合膜抗拉强度最大,达到43 MPa。改性纳米TiO2质量分数为2%的复合膜断裂伸长率最大为13.6%。在模拟溶液质量浓度为20 mg/L时,改性纳米TiO2质量分数为2%的复合膜对亚甲基蓝降解率最大,为51.7%。改性纳米TiO2质量分数为4%的复合膜对甲基橙降解率最大,为42.2%。模拟溶液初始浓度愈高,则复合膜对亚甲基蓝及甲基橙降解率均降低。  相似文献   

11.
Newly synthesized functional nanoparticles, 3-amino-1,2,4-triazole (ATA)/SiO2–TiO2 were introduced to the polyurethane (PU) matrix. Electrochemical techniques were used to investigate the barrier properties of the synthesized PU–ATA/SiO2–TiO2 nanocomposite coated steel specimen. In natural seawater, electrochemical impedance spectroscopy experiments indicated outstanding protective behaviour for the PU–ATA/SiO2–TiO2 coated steel. The coating resistance (Rcoat) of PU–ATA/SiO2–TiO2 was determined to be 2956.90 kΩ·cm–2. The Rcoat of the PU–ATA/SiO2–TiO2 nanocomposite coating was found to be over 50% higher than the PU coating. The current measured along the scratched surface of the PU–ATA/SiO2–TiO2 coating was found to be very low (1.65 nA). The enhanced ATA/SiO2–TiO2 nanoparticles inhibited the entry of electrolytes into the coating interface, as revealed by scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction analysis of the degradation products. Water contact angle testing validated the hydrophobic nature of the PU–ATA/SiO2–TiO2 coating (θ = 115.4°). When the concentration of ATA/SiO2−TiO2 nanoparticles was 2 wt %, dynamic mechanical analysis revealed better mechanical properties. Therefore, the newly synthesised PU–ATA/SiO2–TiO2 nanocomposite provided excellent barrier and mechanical properties due to the addition of ATA/SiO2–TiO2 nanoparticles to the polyurethane, which inhibited material degradation and aided in the prolongation of the coated steel’s life.  相似文献   

12.
采用鞭毛作为生物模板剂制备Cd S/TiO_2复合纳米结构薄膜,采用SEM、XRD、IR、紫外-可见漫反射和电化学工作站等对其结构和光电化学性质进行表征。结果表明,鞭毛的引入不但减小了CdS颗粒尺寸和增大了比表面积,而且改善了复合材料的带隙结构。该薄膜可见光光电催化活性比未加入鞭毛的空白样品高1.4倍。提供了一个利用生物模板剂控制半导体纳米结构单元生长与组装及改善光电性能的简单方法。  相似文献   

13.
为提高聚偏氟乙烯(PVDF)膜的亲水性和强度,将纳米二氧化钛(TiO2)溶胶和纳米氧化铝(γ-Al2O3)按不同比例与聚偏氟乙烯共混,采用相转化法制得共混超滤膜。考察了不同比例的混合纳米粒子对PVDF超滤膜的纯水通量、截留率、力学性能等的影响。并利用扫描电子显微镜(SEM)观察了膜的表面和内部微观结构,红外光谱分析(FTIR)和X射线衍射仪(XRD)考察纳米粒子在PVDF基体中的存在状态,通过对复合膜进行拉力测试研究混合纳米粒子对膜力学性能的影响,并使用接触角测量仪测定膜表面和水之间的接触角来定量分析比较膜表面的亲水性。结果表明,γ-Al2O3/TiO2混合比为1∶2时,膜的性能达到最优,孔隙率为74%,水通量为120 L/(m2.h),截留率为93%,拉力最大负荷为35 N,拉伸应变为22%。  相似文献   

14.
Perylene diimide based organic sensitizers capable of electron generation under illumination were used to initiate gas phase photo reduction reactions on TiO2 thin and thick film surfaces. For comparison [Ru(Bpy)3]2+ dye sensitizers were also studied. The photo reduction of CO2 was carried out under static conditions in the gas phase. TiO2 films were coated on hollow glass beads via a sol–gel procedure. Pt was incorporated on the films either by adding the precursor salt in the sol, Pt(in), or by wet impregnation of calcined film with an aqueous solution of the precursor salt, Pt(on). Organic sensitizers were incorporated on the films by wet impregnation of the film from an aqueous solution. Under UV illumination, the methane yields of platinized TiO2 thin films decreased in the following order: Pt(on)·TiO2 > Pt(in)·TiO2 > TiO2. The presence of organic sensitizers inhibited the catalytic activity of pure and platinized TiO2 thick films under UV illumination. The relative enhancement of the reaction yields in the presence of the organic sensitizer under visible light illumination depended on the presence of Pt as well as the incorporation method of Pt in the TiO2 structure. The reaction yields were better when Pt was impregnated on the TiO2 film than when Pt was incorporated in the Ti sol. On the other hand, pure or platinized TiO2 under visible light illumination was totally inactive indicating the role of the organic dye in generating catalytically active electrons under visible light.  相似文献   

15.
以石墨粉和三氯化钛为原料,通过Hummers和水解法制备得石墨烯/二氧化钛(G/TiO2),将G/TiO2作为填料添加到聚氯乙烯(PVC)中,探究其对PVC薄膜性能的影响.结果表明,添加G/TiO2提高了PVC薄膜的力学性能、抗静电性能和耐紫外老化性能.添加G/TiO2的PVC薄膜的拉伸强度由纯PVC薄膜的12.79 ...  相似文献   

16.
Several Ni-W-P-TiO2 nanocomposite coatings were developed by the sol-enhanced electroplating method. The phase and elemental compositions of coatings were determined, and the surface and cross-section morphology were characterized. The mechanical and corrosion performance were systematically tested. The results revealed the addition of 5 ml·L-1 TiO2 sol caused a compact coating surface, while higher concentrations of TiO2 reduced the coating thickness and led to the inferior surface microstructure. The comparison in physiochemical properties of prepared coatings confirmed the superior performance of the Ni-W-P-TiO2 nanocomposite coating at 5 ml·L-1 TiO2 sol addition. Under this condition, the best mechanical properties were achieved when abrasive wear was the dominating wear-resistance mechanism, and the best corrosion resistance was obtained due to its smooth and compact surface microstructure.  相似文献   

17.
目前具有一维纳米结构的TiO2薄膜在电致变色领域应用主要受限于材料光调制幅度小、响应时间长、循环稳定性差等缺点。为了解决上述问题,本文采用沉积法将B型二氧化钛纳米管(TiO2-B)与氧化石墨烯复合,以TiO2粉末为原料,采用水热法得到钛酸纳米管后,利用沉积法在氟掺杂的氧化锡玻璃(FTO)基底上制备了高透明度、大光调制范围以及优良循环性能的氧化石墨烯复合B型二氧化钛纳米管电致变色薄膜(GO/TiO2)。借助XRD、XPS、Raman、FESEM、HR-TEM等分析手段研究了氧化石墨烯用量对GO/TiO2复合薄膜电致变色性能的影响。研究结果表明,当GO与钛酸纳米管的质量比(GO/钛酸)为7%时,GO/TiO2复合薄膜离子扩散系数为1.46×10-8cm2/s,着色效率值为38.1cm2/C,具有良好的电致变色性能。在-1.6V、633nm处,GO/TiO2电致变色薄膜的光调制幅度可达77%,GO/TiO2薄膜的着色和漂白时间分别为28.6s和4.8s,100次循环后的光调制幅度保持率为96.1%。  相似文献   

18.
壳聚糖对玉米淀粉可食膜性能的影响   总被引:1,自引:0,他引:1  
以玉米淀粉为原料,结合壳聚糖在增塑剂甘油的作用下通过溶液浇铸法制备了玉米淀粉/壳聚糖复合可食薄膜,采用红外光谱和扫描电子显微镜对薄膜结构和微观形貌进行了表征,研究了壳聚糖的含量对薄膜力学性能、水蒸气透过性、阻油性及抗菌性能的影响.结果表明,适量的壳聚糖可以较明显地改善薄膜的力学性能,提高其隔水和阻油性能;壳聚糖与淀粉质...  相似文献   

19.
Resonant wave mixing is a promising technology based on employing non-linear waves to intensify heat and mass transfer and enhancing dispersion processes in mixed materials. In the present work, for the first time, resonant wave mixing was used to prepare film-forming dispersions based on gelatinized maize starch and spherical TiO2 nanoparticles (0.5–1.5 wt%) synthesized by sol–gel technique. Then, nanocomposite films were obtained by solution casting method. The dynamic viscoelastic properties, including relaxation spectra of the film-forming dispersions were investigated by oscillatory squeeze film rheometry, while the structure of the nanocomposite films was studied by X-ray diffraction, FTIR spectroscopy and scanning electron microscopy. The mechanical, water-related and UV-protective properties of the film materials were evaluated. It was shown that nanofiller incorporation enhanced the density of the 3D network structure of a gelatinized starch dispersion. The resonant wave treatment favored homogenous dispersion of the TiO2 nanoparticles in the nanocomposites. All nanocomposite film samples displayed higher tensile strength and lower water vapor permeability in comparison with starch films without the nanofiller. The obtained nanocomposites possessed UV-protective properties, which could be potentially applied to produce biodegradable packaging materials with improved functional characteristics.  相似文献   

20.
吴锫  罗学刚  李科  张思钊 《化工学报》2015,66(5):1939-1946
采用共沉淀法合成的新型光催化剂(Fe-Sr2Bi2O5)与低密度聚乙烯(LDPE)通过熔融共混制备了一种新型光催化降解复合膜(Fe-Sr2Bi2O5/PE)。通过力学性能、接触角、傅里叶变换红外光谱(FT-IR)和场发射扫描电镜(FESEM)等表征手段研究了该催化剂在室温条件下固相光催化降解LDPE复合膜的性能变化。结果表明:Fe-Sr2Bi2O5在紫外光和可见光条件下对LDPE均具有较好的光催化降解能力,其中,紫外灯照射10 d后,Fe-Sr2Bi2O5/PE复合膜断裂伸长保留率低于5%,拉伸强度保留率低于40%,接触角降低22.52°,已完全脆化;同时,LDPE复合膜中出现明显的羰基等降解特征吸收峰和降解孔洞;与Sr2Bi2O5和TiO2相比,Fe-Sr2Bi2O5对LDPE具有更好的降解效果。综上所述,在紫外光和可见光条件下,Fe-Sr2Bi2O5对LDPE具有明显的光催化降解作用,为未来光催化降解聚乙烯(PE)提供了一定的新依据。  相似文献   

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