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1.
The influence of chemical treatments on the properties of cantala fiber as well as on the quality of the interfacial bonding of cantala fiber/rHDPE was investigated. The fibers were treated with alkali, silane, and a combination of both. The results showed that the loss of hemicellulose and lignin after the alkali treatment, and the presence of a silane layer on the fiber surface after the silane or alkali-silane treatment, improved the thermal stability, surface energy, and IFSS. The highest surface energy of 45.37 mN/m was obtained during the alkali treatment (NF12). The alkali-silane treatment with 0.75% wt of silane (NSF075) gave the highest thermal stability and IFSS value.  相似文献   

2.
Surface treatment of fan palm fibers (FPFs) was investigated as a means of improving fiber tensile strength (FTS) and interfacial shear strength (IFSS) of unsaturated polyester (UPR)/FPFs samples. The fibers were treated with sodium hydroxide, silane, and a combined sodium hydroxide and silane. FT-IR spectra and SEM observation indicated the removal of hemicellulose and lignin components after chemical treatments. The alkaline treatment of FPF resulted in the highest tensile strength of 816 MPa. The interfacial shear strength of FPF/UPR samples was increased for all treated FPF. The highest IFSS (4.1 MPa) was obtained for the alkaline-treated FPF/UPR sample.  相似文献   

3.
为提高苎麻纤维与聚丙烯(PP)之间的界面相容性,采用1-辛烯涂层结合常压等离子体射流(APPJ)技术对苎麻纤维表面进行疏水性改性,并研究了改变 2 种方法的处理顺序对改性效果的影响。通过改性前后苎麻纤维的表面形态、润湿性、表面化学成分及苎麻/PP界面剪切强度的变化分析改性效果。实验结果显示,经等离子体处理后再进行1-辛烯涂层处理的苎麻纤维表面的C元素含量提高最明显,且该组苎麻纤维/PP界面剪切强度与未处理组相比提高了近40.0%,而改变处理顺序后得到的苎麻纤维与PP的界面剪切强度仅提高了18.2%。  相似文献   

4.
针对常压等离子体处理过程中水分存在的问题,在空气相对湿度分别为5%、65%和95%时,对超高模量聚乙烯进行常压等离子体处理,测定处理前后纤维的静态接触角以及纤维与树脂间的层间剪切强度,采用原子力显微镜和X射线光电子能谱探测纤维表面的变化.结果表明,处理后纤维表面粗糙度、含氧基团和纤维与树脂间的层间剪切强度增加,静态接触...  相似文献   

5.
ABSTRACT

Sugar palm fiber (SPF) as one of the attractive natural fibers to reinforce matrix is gaining attention. This is largely due to its similar properties when compared with other established natural fibers. The aim of this study is to investigate the effectiveness of sodium bicarbonate as a treatment chemical for SPF in comparison with established alkaline treatment. Both treated and untreated fibers were characterized and it was found that the treated fiber shows an increase in crystallinity, thermal stability, and surface’s roughness when compared with the untreated. Among the two different treatments, SPF treated with alkali has an initial decomposition temperature of 255.47°C, while sodium bicarbonate treated and untreated fibers have 250.19°C and 246.76°C, respectively. In both cases, the thermal stability of the fiber was improved. Also, as revealed by the X-ray diffraction (XRD) analysis, the crystallinity index of SPF treated with alkali and sodium bicarbonate increased by 18.43% and 13.60%, respectively, when compared with untreated fiber. In conclusion, the investigation proved that treatment with the sodium bicarbonate has a significant effect on the physicochemical properties of SPF and the chemical could be an alternative chemical for treating other cellulose fibers.  相似文献   

6.
针对常压等离子体处理过程中水分存在的问题,在空气相对湿度分别为5%、65%和95%时,对超高模量聚乙烯进行常压等离子体处理,测定处理前后纤维的静态接触角以及纤维与树脂间的层间剪切强度,采用原子力显微镜和X射线光电子能谱探测纤维表面的变化。结果表明,处理后纤维表面粗糙度、含氧基团和纤维与树脂间的层间剪切强度增加,静态接触角减小,纤维强度不变。随着环境湿度的增加,纤维静态接触角的减少和纤维与树脂间的层间剪切强度的增加不明显,从而说明在常压等离子体处理拒水性纤维的过程中,空气中的水分有助于提高其处理效果,但不显著。  相似文献   

7.
针对常压等离子体处理过程中存在水分的问题,研究回潮率对常压等离子体处理芳纶效果的影响。回潮率分别为0.5%、3.5%和5.5%的3种芳纶经常压等离子处理后,测定其动态接触角以及纤维与树脂间的层间剪切强度,采用原子力显微镜和X射线光电子能谱探测纤维表面发生的物理和化学变化。结果表明,随纤维回潮率的增加,处理后纤维的前进角和后退角减小,而纤维与树脂间的层间剪切强度、纤维表面的粗糙度以及极性基团增加,从而证明了纤维中水分的存在有助于常压等离子体改善芳纶的表面性能。  相似文献   

8.
In this study borassus and tamarind fruit fibers were extracted and their physical and mechanical properties such as diameter, density, tensile strength and interfacial adhesion strength (IAS) were experimentally determined. To study the effect of alkali treatment, both the fruit fibers were treated with 5% vol. sodium hydroxide solution for 0.5 h, 1 h, 2 h, and 4 h durations. Morphological studies of untreated and alkali treated fibers by using scanning electron microscope (SEM) revealed the presence of the surface impurities on the untreated fiber whereas the same were absent on the treated fibers. Fourier transform infrared spectrometry (FTIR) and X-ray diffraction (XRD) analysis also confirmed the elimination of amorphous hemicellulose of the fibers on treatment. Borassus fruit fine fibers and tamarind fruit fibers treated for 2 h exhibited better mechanical properties and improved IAS with Cashew Nut Shell Liquid (CNSL) -Epoxy matrix.  相似文献   

9.
本文通过对Henequen纤维表面形态进行改性 ,探讨了提高Henequen纤维与聚羟基丁酸 /戊酸酯 (PH BV)树脂复合材料界面剪切强度的方法。采用氢氧化钠溶液处理纤维和稀PHBV溶液预浸纤维 ,增加纤维的表面积和湿润性以增强纤维与基质间的物理化学作用。Henequen纤维 /PHBV复合材料界面剪切强度的大小用微粘结法 (microbond)测试 ,结果表明纤维经碱处理后再预浸处理可使界面剪切强度从未处理情况下的 5 .0 5MPa提高到 9.5 5MPa,增加了 89%。  相似文献   

10.
采用常压等离子体射流(APPJ)在不同处理时阃和功率下对聚对苯撑苯并二噁唑(PBO))纤维进行表面改性,以提高其与环氧树脂基体间的界面粘结性能.通过SEM、XPS和静态接触角测试对处理前后纤维的表面形态、元素组成和表面浸润性能进行分析与表征,并采用Micro-bond测试方法测量纤维/环氧问界面剪切强度IFSS,利用单纤维拉伸测试评价等离子体处理对纤维力学性能的损伤.结果表明:PBO纤维经APPJ处理后,表面浸润性能得到改善,IFSS提高了27.85%~130.96%,而纤维强力损伤很小.  相似文献   

11.
表面改性对黄麻纤维性能的影响   总被引:1,自引:0,他引:1  
采用三种不同的化学处理剂,碱、KMnO4和硅烷偶联剂A-151分别对预处理黄麻纤维进行表面改性,测试了它们的基本性能,借助动态接触角分析了黄麻纤维的表面能变化,并通过SEM观察了不同处理后的纤维表面。研究结果表明:经过碱处理和A-151处理后黄麻纤维的回潮率和细度都明显降低;碱处理后,纤维的拉伸强度提高14.64%:黄麻纤维经过不同的表面处理后,纤维的表面能相应降低,微观结构发生改变。  相似文献   

12.
The aim of this study is to scrutinize the use of Calotropis gigantea bast fibers as potential reinforcement in polymer composites. The bast fibers were extracted from the Calotropis gigantea plant bark and some of them were treated with alkali (5 wt.%) solution. The chemical composition, physico-chemical structural properties of the untreated and the alkali treated Calotropis bast fibers were studied. The results of chemical composition analysis indicated that alkali treatment removed most of the non-cellulose materials as confirmed by the FTIR analysis. The X-ray diffraction results exhibited that the crystallinity index of the alkali treated fibers increased in comparison with the untreated fibers, which agrees with the results obtained in the mechanical tests. The tensile strength and modulus of the alkali treated fibers were found to be higher whereas the elongation at break was lower than the untreated fibers. Thermal stability of alkali treated fibers was lower than that of the untreated fiber. Scanning electron micrographs showed roughening of the surface of the fiber due to the removal of the surface impurities and non-cellulosic components on alkali treatment.It can be concluded that alkali treatment is an effective method to improve the surface and mechanical properties of Calotropis bast fibers to be used in composite materials.  相似文献   

13.
ABSTRACT

In this paper, sisal fibers were modified by different methods such as alkali treatment, γ-aminopropyltriethoxysilane treatment, tetraethylorthosilicate (TEOS) sol-gel treatment, TEOS, and silane combination treatment. The effects of different modification methods on the properties of sisal fibers were studied by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and universal material testing machine. The results show that the combination treatment fiber has the best heat resistance and the most obvious improvement in tensile properties, the tensile strength and modulus increase by 31.58% and 15.82%, respectively.  相似文献   

14.
This study investigates the morphological changes and tensile properties of Alfa fibers extracted mechanically after two treatments namely water retting and alkali treatment. The Scanning Electron Microscopy technique is used in this experimental work. The main observation reveals the decrease of noncellulosic component in the fibers which is inversely proportional to the concentration of sodium hydroxide solution in the case of the alkali treatment. Tensile tests were carried out using tensile machine for determining the tensile properties mainly the tensile strength and the elastic modulus. The tensile strength and young’s modulus of retted fibers are assumed constant. The results relative to the alkalized fibers show an improvement of tensile strength and young’s modulus and are proportional to the sodium hydroxide concentration up to 14%.  相似文献   

15.
This study aims at evaluating the physical properties and effects of fiber treatments of natural fiber reinforced polymer composite’s friction applications. Sugar palm fibers (SPFs) were used as fillers (≤ 150 µm) with phenolic resin to fabricate the composites by the hot press technique. The loading of SPFs varied from 0 to 40 vol.% with an interval of 10 vol.% in phenolic composites. The fibers were treated with sea water for 30 days, and with 0.5 M of alkaline solution for 4 hrs. Rockwell hardness, density, voids content, water/oil absorption, and moisture content were studied. Scanning electron microscopy (SEM) was used to investigate the morphology and interfacial bonding of the fiber-matrix in composites. With an increase in the SPF loading in the composites, the results indicated a decline in Rockwell hardness, an increase in water/oil absorption, and density. It was also observed that higher the density of the composites, lower was the voids content. In terms of physical properties, sea water treatment showed better improvement than alkaline treatment. The outcome of this research indicated that SPFs can be effectively used in reinforcing polymer composites, such as friction composites.  相似文献   

16.
Natural fiber-reinforced polyester composites were prepared using bast fibers as the reinforcement which were extracted from Grewia serrulata trees. Chemical treatments such as alkali pretreatment followed by permanganate treatment, acetylation and silane treatment were exclusively applied to modify the fiber surface. Hand lay-up technique with compression molding was adapted for the fabrication of axially oriented fiber reinforced composites. Tensile, flexural and impact strength properties of the specimens prepared were evaluated following the standard procedures. The SEM images of the fractured surfaces shows improvement in compatibility between the chemically treated fibers and the matrix. It was found that the tensile and flexural strengths of chemically treated fiber-reinforced polyester composites have significantly improved when compared to untreated fiber-reinforced polyester specimens. The properties of 1200 hrs water aged specimens were found deteriorated considerably due to diffusion of water into the composite material system. The chemical treatment of fibers prior to fabrication of composites improves the resistance to water absorption tendencies.  相似文献   

17.
竹原纤维的化学脱胶工艺   总被引:4,自引:2,他引:2       下载免费PDF全文
王春红  王瑞  于飞 《纺织学报》2007,28(4):26-29
采用纤维膨化、浸酸、碱煮及柔化整理工艺对竹原纤维进行化学脱胶处理,并对浸酸和碱煮工艺中溶液浓度、处理温度、时间和浴比进行优化设计,提取出可适用于非织造或复合材料工业的纺织纤维。对处理前后纤维的纵向结构进行扫描电镜分析,并对纤维的拉伸断裂强度进行测试与评价,确定出最佳处理工艺。结果表明:酸碱处理过程中溶液的质量浓度对纤维的拉伸性能影响最大,当酸碱质量浓度分别为1.58、g/L时,竹原纤维的拉伸强度可达到5.5 cN/dtex,比处理前提高了近27倍,且柔软度提高1倍,可被梳理成均匀的纤维网。  相似文献   

18.
Experimental investigations are conducted to study the effectiveness of protective coating with cashew nut shell liquid (CNSL) on coir. CNSL solution has been applied on suitably pretreated coir yarns and coating concentrations are optimized to reduce moisture absorption and microbial growth. Two common cellulose and lignin degrading fungi (Aspergillus niger and Rhizopus stolonifer) have been taken as test organisms. Qualitative and quantitative analyses are carried out to measure fungal growth on untreated and treated fibers. The study shows that treated fibers inhibit the development of fugal growth on fiber surface by 95%. The reduced moisture absorption and improved hydrophobicity of the treated yarns are also reported. Increase in tensile strength up to 17% is noticed. The better properties achieved are explained on the basis of selection of the coating methodology and also the interfacial features of the coatings with the coir fiber. The results indicate the possibility of future application of such treated fibers in geotextiles having better performance compared to the untreated counterparts.  相似文献   

19.
为制备含磷无卤阻燃聚丙烯腈纤维,利用KOH 水溶液对丙烯腈(AH) 醋酸乙烯酯(VAc)无规共聚物(P(AN?co?VAc))纤维中的VAc单元进行选择性水解,再与O,O?二乙基磷酰氯进行磷酰化反应制得阻燃聚丙烯腈纤维。采用傅里叶变换红外光谱、差示扫描量热和热重分析法对阻燃纤维结构及热性能进行表征,利用扫描电子显微镜对阻燃聚丙烯腈纤维的炭残渣进行分析。结果表明:随水溶液pH值的升高,聚丙烯腈纤维中VAc单元迅速水解;聚丙烯腈纤维中VAc单元的存在使共聚纤维环化放热分解峰值温度增大,当VAc单元的质量分数为30%时,可达287℃,而阻燃聚丙烯腈纤维的该温度高达340℃;阻燃聚丙烯腈纤维在800℃ 时的炭残渣量高达48%以上,远高于共聚合聚丙烯腈纤维41%的残炭量,具有良好的成炭性。  相似文献   

20.
利用注射成形工艺制备了旧报纸纤维(NRF)/聚乳酸(PLA)复合材料,探讨了碱处理对NRF/PLA复合材料力学性能的影响。结果表明,碱处理可使旧报纸纤维中部分半纤维素和果胶等物质溶出,纤维表面极性降低,旧报纸纤维与聚乳酸相容性得到改善;碱处理后的旧报纸纤维纤维素结晶度增大,纤维表面孔径增大,比表面积增加,纤维表面油墨被去除,旧报纸纤维与聚乳酸界面结合性能得到改善,NRF/PLA复合材料力学性能提高。  相似文献   

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