聚丙烯腈纳米纤维增强聚氨酯基复合膜的制备及其力学性能的研究

利用静电纺丝制备聚丙烯腈/聚氨酯(PAN/PU)复合纳米纤维膜,通过热处理复合纳米纤维膜制备聚丙烯腈纳米纤维增强聚氨酯基(PANNFs/PU)复合膜。采用扫描电子显微镜(SEM)分析PAN/PU复合纳米纤维膜热处理前后的形貌结构,采用多功能拉伸仪测试纤维膜热处理前后的力学性能。分析发现,PANNFs/PU复合膜力学性能受混纺溶液中占比多的一方影响,当混纺溶液中PAN和PU质量比为4∶6时,得到的PANNFs/PU复合膜断裂应力达到152.1 MPa,断裂伸长达到178.8%,较其他质量比PANNFs/PU复合膜,整体所表现的力学性能佳;当混纺溶液PAN和PU质量比为4∶6时,混纺溶液质量分数增加到18%时,和PAN/PU复合纳米纤维膜相比,PANNFs/PU复合膜断裂应力增长了3倍左右,达到217.8 MPa,断裂伸长增长了2.5倍左右,达到320.9%。     

静电纺PAN纳米纤维多孔膜的微观结构与过滤性能

将不同质量分数的聚丙烯腈( PAN)纺丝液进行静电纺丝,制备了PAN纳米纤维多孔膜,并对静电纺PAN纳米纤维膜的形貌、纤维直径、孔隙率和比表面积、力学性能以及过滤性能进行表征和测试.结果表明,随着PAN质量分数的增加,纤维的平均直径明显增加;对应的静电纺多孔纤维膜的孔隙率和比表面积都减小、过滤效率降低.其中,由PAN质...     

空气过滤用聚丙烯腈静电纺纤维膜的制备及其性能

为开发用于空气过滤的纳米纤维,采用静电纺丝技术制备了聚丙烯腈(PAN)纳米纤维膜,探讨了其纺丝液质量分数及纺丝电压对所纺纤维微观形貌的影响,同时研究了纤维膜厚度对过滤效率和压降的影响。实验结果表明:PAN纺丝液质量分数为12%,纺丝电压为20 k V时,所得纤维粗细均匀,平均直径为230 nm;当纤维膜厚度由18μm增至35μm时,过滤压降则由121.93 Pa升至591.75 Pa,而过滤效率由81.78%升至99.24%。对过滤性能较好的纤维膜分别进行力学性能和泡压法滤膜孔径测试,测得此纤维膜的弹性模量为223.67 MPa,断裂伸长率为51.96%,拉伸断裂应力为5.93 MPa,拉伸强度为7.77 MPa,拉伸屈服应力为2.79 MPa,平均孔径为2.064 3μm。     

三层自增强PAN纳米纤维复合锂离子电池隔膜的制备与电化学性能研究

利用静电纺丝技术,通过改变转鼓转速,制备并复合形成三层自增强PAN纳米纤维复合隔膜。研究不同转鼓转速下所得中间层用PAN纳米纤维膜的排列及形貌特点,测试三层自增强PAN纳米纤维复合隔膜的物理力学性能及电化学性能,以评价其综合表现。结果表明:当中间层的转鼓转速为700 r/min时,制备的三层自增强PAN纳米纤维复合隔膜在纵向(即收集方向)的拉伸断裂强度达到最大,为13.10 MPa;室温下的孔隙率和吸液率分别为78.3%和356.3%,20℃下的离子电导率高达0.63 m S/cm,电化学稳定电压达到5.0 V,电化学稳定性优异;由其制备的锂离子电池拥有较高的首次放电比容量值,达138.4 m A·h/g。三层自增强PAN纳米纤维复合隔膜的综合性能能够满足锂离子电池的需要。     

热处理对聚丙烯腈/聚环氧乙烷复合纳米纤维膜的力学性能影响研究

采用静电纺丝法制备了聚丙烯腈和聚环氧乙烷纳米纤维膜,依次放置于方舟之上,热处理后得到了聚丙烯腈/聚环氧乙烷(PAN/PEO)复合纳米纤维膜,通过TG、SEM、多功能拉伸仪等研究了热处理温度和压力对复合纳米纤维膜形貌、力学性能的影响。结果表明:在140℃、20kPa压强的条件下得到的PAN/PEO纳米纤维膜保持了静电纺纳米纤维膜多孔的特点;在100℃、20kPa压强条件下得到的PAN/PEO纳米纤维膜具有较佳力学性能。     

PU/PVDF防水透气共混膜的制备及性能研究

采用静电纺丝法制备聚氨酯/聚偏氟乙烯(PU/PVDF)共混纳米纤维膜,研究PU、PVDF质量分数、溶剂体积配比、溶质质量比对纳米纤维形貌、直径及膜性能的影响,探索共混纤维膜较优制备工艺。结果表明:共混纳米纤维膜较优制备工艺为静电纺丝电压14 kV、接收距离10 cm、纺丝液质量分数12%、溶剂体积配比N,N-二甲基甲酰胺/丙酮为4/6、溶质质量比PU/PVDF为7/3,此条件下可获得具有较优防水透气性能和力学性能的共混膜。     

扩链时间对聚氨酯及其静电纺纳米纤维性能的影响

为了优化聚氨酯纳米纤维膜的力学性能和润湿性能,以聚四氢呋喃醚二醇(PTMG)、4,4′-亚甲基双(苯基异氰酸酯)(4,4′-MDI)和1,4-丁二醇(BDO)为主要原料合成聚氨酯(PU),并利用静电纺丝技术制备PU纳米纤维膜。研究了不同扩链段反应时间对合成聚氨酯物理性质和静电纺纳米纤维膜性能等的影响。采用红外光谱仪(FTIR)、高效液相色谱仪(GPC)、热重分析仪(TG)、扫描电子显微镜(SEM)、多功能拉伸仪和动态/静态接触角仪对PU结构和纤维膜的形貌性能进行表征。结果表明：当扩链反应时间由90 min增加至120 min时,聚氨酯分子量增加,合成聚氨酯的热稳定性略有提高,纳米纤维的成膜性能增强。当扩链反应时间为120 min时,纳米纤维膜的断裂应力为6.8 MPa,断裂伸长率达到139%;疏水性能随着扩链反应时间的增加明显提高,当扩链反应时间为120 min时,240 s后水接触角仍然高达112°。     

高过滤性能石墨烯复合纳米纤维膜的制备及性能

将石墨烯(GR)纳米颗粒掺杂到聚丙烯腈(PAN)纺丝溶液中,利用静电纺丝技术制备石墨烯/聚丙烯腈(GR/PAN)复合纳米纤维膜。研究PAN质量分数、GR用量、纺丝电压及接收距离对GR/PAN复合纳米纤维膜形貌和过滤性能的影响,发现最优纺丝工艺参数为PAN质量分数14.0%、GR用量1.5%、纺丝电压26 kV、接收距离14 cm、注射速度1 mL/h。此最优纺丝工艺参数制备的GR/PAN复合纳米纤维膜的过滤效率为98.86%,过滤阻力为110.30 Pa。     

热诱导熔接聚氨酯/聚二甲基硅氧烷防水透湿膜的制备及其性能优化

为提高纳米纤维膜的防水、透湿和力学性能,在聚氨酯(PU)纺丝液中添加无氟疏水剂聚二甲基硅氧烷(PDMS),采用静电纺丝法制备静电纺PU/PDMS防水透湿膜,并在此基材上采用静电喷雾法沉积PU/PDMS微球制备静电喷雾PU/PDMS防水透湿膜;利用热诱导工艺分别对静电纺PU/PDMS和静电喷雾PU/PDMS防水透湿膜进行热处理改性,研究了热处理温度和时间对其形貌、孔径分布、防水性能、透气透湿性能及力学性能的影响,并对其影响机制进行分析。结果表明：静电喷雾PU/PDMS防水透湿膜的防水透湿性能优于静电纺PU/PDMS防水透湿膜,但经热处理后由于膜内部产生更多粘连,导致孔隙率降低,防水透湿性能出现下降;热处理后静电纺PU/PDMS防水透湿膜的孔径大大降低,并使其串珠结构向蛛网结构转化,防水性能和力学性能显著提升,当加热温度为100℃,加热时间为90 min时,其水接触角达到144.7°,透湿率为5 666.7 g/(m²·d),透气率为9.91 mm/s,断裂强度为17.9 MPa,断裂伸长率为210.7%。     

基于不同纺丝参数下取向纳米纤维的制备及取向度分析

为了探讨溶液性能及纺丝参数对静电纺取向纳米纤维形态的影响,制备不同质量分数的聚丙烯腈(PAN)溶液和加入不同质量分数LiCl的PAN溶液,对溶液黏度和电导率进行测试,并利用旋转的滚筒制备了不同的取向纳米纤维。研究表明:PAN溶液黏度和电导率都随着溶液质量分数的增加而增加,且黏度呈指数增加;而随着LiCl质量分数的增加,PAN溶液的黏度略有下降,而电导率显著增加。相同滚筒转速(2000 r/min)下,PAN纳米纤维的取向排列程度随着溶液质量分数的增加先提高后降低,12%的PAN纳米纤维的取向排列程度最好;而随着LiCl质量分数的增加,PAN纳米纤维的取向排列程度增加。当滚筒转速从1500 r/min增加到2500 r/min,纳米纤维的取向排列程度也增加了。     

取向增强复合锂离子电池隔膜的制备及其性能

为获得纵向拉伸性能优异的静电纺丝锂离子电池隔膜,首先在不同转速条件下制备聚丙烯腈（PAN）纤维膜,分析得出在700 r/min 时,PAN 纤维排列取向性最好。然后将在700 r/min 条件下制备得到的PAN 增强层纤维膜作为中间层,结合上下2 层杂乱分布的聚酯（PET）纤维膜形成取向增强复合隔膜,在低速（100 r/min）条件下制备了PET/PAN/PET 各向同性纤维膜作为对比膜。表征了2 种隔膜的物理力学性能及电化学性能。结果表明：取向增强复合隔膜的吸液率为371%,热收缩率为4.1%,室温下离子电导率为0.553 ms/cm,电化学稳定窗口为5.27 V;由其制备的电池首次放电比容量为138.0 mA?h/g;纵向拉伸断裂强度为9.2 KPa,比对比膜提高了130%,该取向增强复合隔膜机械强度显著提高,综合性能优于PET/PAN/PET 各向同性纤维膜。     

聚丙烯腈/羧基丁苯乳胶复合纳米纤维膜的制备及其性能

为提高静电纺聚丙烯腈(PAN)纳米纤维膜的力学性能,将羧基丁苯乳胶(SBR)与PAN纳米纤维膜通过溶液浸泡进行复合,制备了一系列PAN/SBR复合纳米纤维膜,研究了SBR质量分数对PAN纳米纤维膜表面形貌、化学结构、润湿性能、热性能和力学性能的影响.结果表明:SBR以物理粘结的形式与PAN纳米纤维膜复合在一起,随着SB...     

仿星型拓扑几何结构聚氨酯/聚二甲基硅氧烷防水透湿膜制备与性能

为提高纳米纤维膜的防水性并探究膜表面微观结构对膜性能的影响机制,采用高可纺性的聚氨酯(PU)和无氟、低表面能的聚二甲基硅氧烷(PDMS)为原料,通过静电纺丝法制备了PU/PDMS纳米纤维膜,然后在该纤维膜基材上采用静电喷雾法沉积PU/PDMS微颗粒得到对环境友好的防水透湿膜,对其形貌、防水性能、透气透湿性能和力学性能进...     

魔芋葡甘聚糖-普鲁兰多糖复合膜的制备与性能研究

利用魔芋葡甘聚糖(KGM)和普鲁兰多糖(PUL)制备可食性复合膜,研究了KGM与PUL不同配比对复合膜性能的影响。结果表明,KGM和PUL分子之间发生了氢键相互作用,有较好的相容性,复合膜的拉伸强度、断裂伸长率以及阻湿性能和纯膜比较都显著提高。当KGM与PUL复合比为6∶4(w/w)时,复合膜的热稳定性最好,其拉伸强度和断裂伸长率最大,分别为77.68 MPa和14.93%,水蒸气透过率较纯KGM膜降低了34%,氧气透过率高于纯KGM膜,但符合食品包装膜的要求。复合膜的性能优于纯KGM膜以及纯PUL膜,适合应用于可食性食品包装膜材料。      

酸解淀粉/PBAT复合膜的制备及其性能研究

为了提高淀粉基复合膜的力学性能和阻水性能,以酸解淀粉和聚己二酸-对苯二甲酸丁二醇酯（PBAT）为主要成膜基材,通过挤出吹塑法制备了酸解淀粉/PBAT复合膜,研究了淀粉/PBAT比例对复合膜结构、力学性能和阻隔性能等的影响。结果表明,随着PBAT含量的增加,淀粉/PBAT共混物的流动性增强,模量与复合黏度降低,淀粉与PBAT之间的氢键作用减弱。添加PBAT可显著提高淀粉膜的力学性能和阻隔性能,复合膜纵向最大拉伸强度和断裂伸长率分别为7.86 MPa和532.67%,最低水蒸气和氧气透过系数分别为3.74×10?11 g?m?1?s?1?Pa?1和5.77×10?15 cm2?s?1?Pa?1。     

转谷氨酰胺酶对乳清浓缩蛋白-纳米微晶纤维素复合膜性能的影响

为了研究转谷氨酰胺酶(TG)对乳清浓缩蛋白(WPC)-纳米微晶纤维素(NCC)复合膜性能和结构的影响,本研究以WPC和NCC为原料,利用TG酶处理对WPC-NCC复合膜的机械性能和屏障性能进行优化,并探究TG酶的交联作用对乳清蛋白分子二级结构和复合膜成膜微观结构的作用情况。结果表明,在TG酶的添加量达到12 U/g_蛋白时,WPC-NCC复合膜的抗拉强度达到2.25 MPa,断裂伸长率达到86.75%,水蒸气透过率为4.40×10^-12 gmPa^-1s^-1m^-2,有效改善了WPC-NCC复合膜的机械性能性和水蒸气屏障性能。经过TG酶的处理,乳清蛋白结构向稳定有序的方向转变,减少了复合膜的孔洞数量和孔径,使成膜表面结构更加致密,促进了复合膜的机械性能和水蒸气屏障性能的提升。     

Effects of various plasticizers and nanoclays on the mechanical properties of red algae film

To manufacture red algae (RA) film, we used various plasticizers such as glycerol, sorbitol, sucrose, fructose, and polypropylene glycol (PPG), and then determined the mechanical properties of the RA films. The tensile strength (TS), elongation at break (E), and water vapor permeability (WVP) of the films containing various plasticizers ranged between 0.43 to 9.10 MPa, 10.93% to 47.17%, and 1.28 to 1.42 ng m/m2sPa, respectively. RA films containing fructose as a plasticizer had the best mechanical properties of all the films evaluated. Incorporation of nanoclay (Cloisite Na+ and 30B) improved the mechanical properties of the films. RA film with 3% Cloisite Na+ had a TS of 10.89, while RA film with 30B had a TS of 10.85 MPa; these films also had better E and WVP values than the other RA films evaluated. These results suggest that RA/nanoclay composite films are suitable for use as food packaging materials. PRACTICAL APPLICATION: Edible RE/nanoclay composite films prepared in the present investigation can be applied in food packaging.     

高抗菌性聚乙烯醇/Ag@MOF食品包装膜的制备与表征

为分析银基金属有机框架(Ag@MOF)用于食品包装的可行性,采用流延法制备四种不同的聚乙烯醇(PVA)基食品包装膜(PVA/Ag@MOF、PVA/H₂PYDC、PVA/Ag、PVA),并研究它们的力学性能、热力学性能、水阻隔性、抗菌性、细胞毒性等。结果表明,与PVA、PVA/H₂PYDC膜相比,Ag@MOF的加入改善了薄膜的力学性能,使薄膜最大拉伸强度提高到36.21 MPa。与PVA、PVA/H₂PYDC、PVA/AgNPs膜相比,Ag@MOF的加入增强了膜的热稳定性。与PVA、PVA/H₂PYDC膜相比,AgNPs和Ag@MOF的刚性结构防止了水的扩散,提高了阻水性能。PVA/Ag@MOF膜对金黄色葡萄球菌和大肠杆菌的抗菌活性也很好,其抗菌活性远大于AgNPs和H₂PYDC复合膜,且具有较低的细胞毒性。因此,PVA/Ag@MOF薄膜是一种很有前景的食品包装材料,可以减少环境微生物对食品的干扰且细胞毒性较低,能够有效提高食品的安全性和储存周期。     

Physical and Mechanical Properties of Durum Wheat (Triticum durum) Starch Films Prepared with A‐ and B‐type Granules

The use of starch for the production of biodegradable materials has been increasing. Wheat is an important source, however, durum wheat starch and its separated granular components had not been evaluated for this purpose. The aim of this study was to evaluate the physical and mechanical properties of durum wheat starch films when prepared with a distribution of different granular‐sized starches (A‐ and B‐type). Starch was isolated, and the A and B populations of granules were separated. Films were prepared by casting. Glycerol (G) was used as a plasticizer in concentrations of 25% and 40%, respectively. Starch films were evaluated using scanning electron microscopy (SEM), mechanical properties (tensile strength, TS, elongation at break, E, elastic modulus, EM), solubility, and X‐ray diffraction (XRD). Durum wheat starch films were transparent, flexible, and, according to SEM, highly homogeneous. Films prepared with 25% G showed brittle material behavior (TS = 42–50 MPa, E = 1.4–2.7%, and EM = 31–34 MPa), whereas those prepared with 40% G had ductile material characteristics (TS = 11–17 MPa, E = 4–41%, and EM = 4–11.3 MPa). These mechanical properties of the films were significantly affected by the glycerol concentration and the starch granule type used. The film solubility was low when compared to those reported in other studies. It increased with increasing plasticizer concentration. According to the XRD, the films showed a semi‐crystalline structure.     

Characterization of fish protein films incorporated with essential oils of clove,garlic and origanum: Physical,antioxidant and antibacterial properties

Consumers are demanding high quality foods using environmental-friendly packaging systems and natural preservatives, like edible/biodegradable films or coatings with bioactive properties. In this context, films prepared with Cape hake by-products proteins were combined with three essential oils (garlic, clove, and origanum) and characterized in terms of physical, mechanical, antioxidant, and antibacterial properties. Control films, without essential oils, were homogeneous, transparent, slightly yellow, and mechanically resistant. The incorporation of garlic, clove, and origanum essential oils in this film significantly decreased thickness, water solubility, breaking force and elongation, whereas increased the free radical scavenging activity of films. Particularly, clove films showed lower water vapour permeability than control films, and the highest antibacterial activity (against Shewanella putrefaciens). Garlic films were the most yellowish and had the highest antioxidant activity. Finally, origanum films were rather similar to the control, particularly in colour, transparency and reducing power. In conclusion, proteins recovered from Cape hake by-products combined with essential oils have adequate properties with applicability in new preservation food packaging systems.