In this study,bamboo nanoparticles in concentration ranges from 0-5%were incorporated along with woven/nonwoven kenaf fiber mat into unsaturated polyester and the developed composites were further characterized.Bamboo...In this study,bamboo nanoparticles in concentration ranges from 0-5%were incorporated along with woven/nonwoven kenaf fiber mat into unsaturated polyester and the developed composites were further characterized.Bamboo chips were subjected to ball milling process for the synthesis of nanoparticles with a particle size of 52.92 nm.The effect that the incorporation of nanoparticles had on various properties of reinforced composites was further observed.Due to the high surface area of nanoparticles,incorporation of 3%of nanofillers contributed towards strong bonding and better wettability with matrix,thus resulting in excellent mechanical properties and thermal characteristics in reinforced unsaturated polyester composites.Furthermore,mechanical characteristics of reinforced composites were deteriorated by the addition of a higher percentage of nanoparticles(>3%)due to agglomeration,as confirmed by scanning electron microscopy.Moreover,ordered structural arrangement of woven kenaf textile fiber showed enhancement in interfacial adhesion and promoted superior mechanical strength in reinforced composites as compared with nonwoven composites.展开更多
The present work emphasizes the isolation of cellulose nanofiber(CNF)from the kenaf(Hibiscus cannabinus)bast through a chemo-mechanical process.In order to develop high CNF yield with superior properties of CNF for im...The present work emphasizes the isolation of cellulose nanofiber(CNF)from the kenaf(Hibiscus cannabinus)bast through a chemo-mechanical process.In order to develop high CNF yield with superior properties of CNF for improving compatibility in varied applications this method is proposed.The fiber purification involved pulping and bleaching treatments,whereas mechanical treatment was performed by grinding and high-pressure treatments.The kraft pulping as a delignification method followed by bleaching has successfully removed almost 99%lignin in the fiber with high pulp yield and delignification selectivity.The morphology of the fibers was characterized by scanning electron microscopy,which showed a smooth surface,fiber bundles,gel-shaped nanofiber,and an average size of 94.05 nm with 69%of CNF in 34–100 nm size.The chemo-mechanical process exhibited a more crystalline nature in CNF than pulp kenaf.The low zeta potential values exhibit the distribution of fibrils and colloidal suspension stability without any further agglomeration.A lower concentration of CNF is less stable exhibiting the product agglomeration.Therefore,the chemo-mechanical process for the isolation of CNF(Hibiscus cannabinus)from kenaf involves sustainable,low-cost,non-toxic,and cheap alternatives than other traditional methods.展开更多
In this study,pineapple leaf fiber(PALF),kenaf fiber(KF)and PALF/KF/phenolic(PF)composites were fabricated and their mechanical properties were investigated.The mechanical properties(tensile,flexural and impact)of the...In this study,pineapple leaf fiber(PALF),kenaf fiber(KF)and PALF/KF/phenolic(PF)composites were fabricated and their mechanical properties were investigated.The mechanical properties(tensile,flexural and impact)of the PALF/KF/PF hybrid composites were investigated and compared with PALF/KF composites.The 3P7K exhibited enhanced tensile strength(46.96 MPa)and modulus(6.84 GPa),flexural strength(84.21 MPa)and modulus(5.81 GPa),and impact strength(5.39 kJ/m2)when compared with the PALF/PF and KF/PF composites.Scanning electron microscopy(SEM)was used to observe the fracture surfaces of the tensile testing samples.The microstructure of the 7P3K hybrid composite showed good interfacial bonding and the addition of KF improved the interfacial strength.It has been concluded that the 3P7K ratio allowed obtaining materials with better mechanical properties(tensile,flexural and impact strengths)than PALF/PF and KF/PF composites.The results obtained in this study will be used for further comparative study of untreated hybrid composites with treated hybrid composites.展开更多
Cellulose whiskers were isolated from kenaf (Hibiscus cannabinus L.) bast fibers via sulfuric acid and hydrochloric acid hydrolysis. Raw kenaf bast, NaOH treated, bleached fibers, sulfuric acid whiskers (SAW) and hydr...Cellulose whiskers were isolated from kenaf (Hibiscus cannabinus L.) bast fibers via sulfuric acid and hydrochloric acid hydrolysis. Raw kenaf bast, NaOH treated, bleached fibers, sulfuric acid whiskers (SAW) and hydrochloric acid whiskers (HClW) morphology, functional groups, crystallinity, and thermal stability were characterized. The TEM images showed that the sulfuric acid and HCl whiskers have average diameters and length range of 3 nm and 100 - 500 nm, respectively. The FTIR study indicated that during the conversion process, most of the hemicellulose and almost all the lignin were removed by the NaOH and subsequent bleaching treatments. The crystallinity of HCl whiskers was found to be higher (84%) than that of sulfuric acid whiskers (72%). Thermogravimetric analysis indicated that HCl whiskers had better thermal stability than the sulfuric acid ones. In addition, a two-stage decomposition behavior was revealed by TGA in the sulfuric acid whiskers because of incorporation of the sulfate group with the cellulose crystals.展开更多
The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable app...The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing.展开更多
In this paper, we deals with mechanical performance of resin impregnation with natural fiber and fiber reinforced composites. The effect of the addition of a rein impregnation process on static strength of the injecti...In this paper, we deals with mechanical performance of resin impregnation with natural fiber and fiber reinforced composites. The effect of the addition of a rein impregnation process on static strength of the injection molded composites was investigated by carrying out tensile and banding tests, followed by Scanning electron microscopy (SEM) observation of fiber surface and fracture surface of composites. The tensile strength of natural fiber and natural fiber reinforced composites with resin impregnation method increases with Polyvinyl alcohol (PVA) impregnation. In addition, Phenol resin impregnation recovers fiber tensile strength after alkali treatment. Resin impregnation causes decrease in contact surface area;however, it does not cause decrease in mechanical properties. Our results suggest that the using rein impregnation method has better effect on the mechanical properties of natural fiber reinforced Polypropylene (PP) composites.展开更多
The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,break...The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,breaking strength, breaking elongation and linear density of aerobic retted kenaf bundle fibers did not show significantly difference with that of anaerobic retted kenaf bundle fibers by ANOVA-Tukey's studentized test at a = 5% except for the softness. The bioenergetic principle and the calculation of the amount of ATP produced during the decomposition processing of kenaf gums were used to explain why the retting duration in the case of using aerobic microbes was much shorter than that of using anaerobic microbes.展开更多
This paper deals with the chemical treatment of kenaf fi-ber and the spinning of the kenaf yarn blended with cot-ton. The experimental results show that after being treated by alkli, the properties of kenaf fiber have...This paper deals with the chemical treatment of kenaf fi-ber and the spinning of the kenaf yarn blended with cot-ton. The experimental results show that after being treated by alkli, the properties of kenaf fiber have im-proved obviously, which made it possible to produce the yarn of kenaf blended with cotton. The results are very helpful for the utilization of kenaf fiber.展开更多
为探寻适合红麻纤维蒸气爆破预处理与酶解糖化的技术参数,开展红麻纤维气爆压力、保压时间、填料量等蒸气爆破预处理技术参数研究,并对蒸气爆破预处理后的红麻纤维进行浴比、酶解时间、酶种类、酶配比、酶用量等酶解糖化单因子试验与正...为探寻适合红麻纤维蒸气爆破预处理与酶解糖化的技术参数,开展红麻纤维气爆压力、保压时间、填料量等蒸气爆破预处理技术参数研究,并对蒸气爆破预处理后的红麻纤维进行浴比、酶解时间、酶种类、酶配比、酶用量等酶解糖化单因子试验与正交试验。结果表明:红麻纤维气爆预处理以填料量100%、气爆压力2.5 MPa、保压时间240~300 s的效果较好;红麻纤维酶解糖化的较优工艺参数为浴比(1∶5.00)^(1∶7.50),纤维素酶和木聚糖酶的配比2∶3,采用混合酶(1.50%纤维素酶+2.250%木聚糖酶),p H 5.0,糖化率可达70%以上。展开更多
文摘In this study,bamboo nanoparticles in concentration ranges from 0-5%were incorporated along with woven/nonwoven kenaf fiber mat into unsaturated polyester and the developed composites were further characterized.Bamboo chips were subjected to ball milling process for the synthesis of nanoparticles with a particle size of 52.92 nm.The effect that the incorporation of nanoparticles had on various properties of reinforced composites was further observed.Due to the high surface area of nanoparticles,incorporation of 3%of nanofillers contributed towards strong bonding and better wettability with matrix,thus resulting in excellent mechanical properties and thermal characteristics in reinforced unsaturated polyester composites.Furthermore,mechanical characteristics of reinforced composites were deteriorated by the addition of a higher percentage of nanoparticles(>3%)due to agglomeration,as confirmed by scanning electron microscopy.Moreover,ordered structural arrangement of woven kenaf textile fiber showed enhancement in interfacial adhesion and promoted superior mechanical strength in reinforced composites as compared with nonwoven composites.
基金Ministry of Education,Culture,Research and Technology(KEMENDIKBUDRISTEK)Republic of Indonesia,for providing the Research Grant“Basic Research Scheme”No.110/E5/PG.02.00.PL/2023.
文摘The present work emphasizes the isolation of cellulose nanofiber(CNF)from the kenaf(Hibiscus cannabinus)bast through a chemo-mechanical process.In order to develop high CNF yield with superior properties of CNF for improving compatibility in varied applications this method is proposed.The fiber purification involved pulping and bleaching treatments,whereas mechanical treatment was performed by grinding and high-pressure treatments.The kraft pulping as a delignification method followed by bleaching has successfully removed almost 99%lignin in the fiber with high pulp yield and delignification selectivity.The morphology of the fibers was characterized by scanning electron microscopy,which showed a smooth surface,fiber bundles,gel-shaped nanofiber,and an average size of 94.05 nm with 69%of CNF in 34–100 nm size.The chemo-mechanical process exhibited a more crystalline nature in CNF than pulp kenaf.The low zeta potential values exhibit the distribution of fibrils and colloidal suspension stability without any further agglomeration.A lower concentration of CNF is less stable exhibiting the product agglomeration.Therefore,the chemo-mechanical process for the isolation of CNF(Hibiscus cannabinus)from kenaf involves sustainable,low-cost,non-toxic,and cheap alternatives than other traditional methods.
文摘In this study,pineapple leaf fiber(PALF),kenaf fiber(KF)and PALF/KF/phenolic(PF)composites were fabricated and their mechanical properties were investigated.The mechanical properties(tensile,flexural and impact)of the PALF/KF/PF hybrid composites were investigated and compared with PALF/KF composites.The 3P7K exhibited enhanced tensile strength(46.96 MPa)and modulus(6.84 GPa),flexural strength(84.21 MPa)and modulus(5.81 GPa),and impact strength(5.39 kJ/m2)when compared with the PALF/PF and KF/PF composites.Scanning electron microscopy(SEM)was used to observe the fracture surfaces of the tensile testing samples.The microstructure of the 7P3K hybrid composite showed good interfacial bonding and the addition of KF improved the interfacial strength.It has been concluded that the 3P7K ratio allowed obtaining materials with better mechanical properties(tensile,flexural and impact strengths)than PALF/PF and KF/PF composites.The results obtained in this study will be used for further comparative study of untreated hybrid composites with treated hybrid composites.
文摘Cellulose whiskers were isolated from kenaf (Hibiscus cannabinus L.) bast fibers via sulfuric acid and hydrochloric acid hydrolysis. Raw kenaf bast, NaOH treated, bleached fibers, sulfuric acid whiskers (SAW) and hydrochloric acid whiskers (HClW) morphology, functional groups, crystallinity, and thermal stability were characterized. The TEM images showed that the sulfuric acid and HCl whiskers have average diameters and length range of 3 nm and 100 - 500 nm, respectively. The FTIR study indicated that during the conversion process, most of the hemicellulose and almost all the lignin were removed by the NaOH and subsequent bleaching treatments. The crystallinity of HCl whiskers was found to be higher (84%) than that of sulfuric acid whiskers (72%). Thermogravimetric analysis indicated that HCl whiskers had better thermal stability than the sulfuric acid ones. In addition, a two-stage decomposition behavior was revealed by TGA in the sulfuric acid whiskers because of incorporation of the sulfate group with the cellulose crystals.
基金the Tenure Track Position“Bois:Biobased materials”part of E2S UPPA supported by the“Investissements d’Avenir”French Program managed by ANR(ANR-16-IDEX-0002).
文摘The chemical composition and thermal properties of natural fibers are the most critical variables that determine the overall properties of the fibers and influence their processing and use in different sustainable applications,such as their conversion into bioenergy and biocomposites.Their thermal and mechanical properties can be estimated by evaluating the content of cellulose,lignin,and other extractives in the fibers.In this research work,the chemical composition and thermal properties of three fibers,namely bagasse,kenaf bast fibers,and cotton stalks,were evaluated to assess their potential utilization in producing biocomposites and bioenergy materials.The chemical composition analysis followed the Technical Association of the Pulp and Paper Industry Standards(TAPPI)methods.The total phenol content was quantified using the Folin-Ciocalteu method,while Fourier Transform Infrared Spectroscopy(FTIR)was employed to assess the light absorption by the bonds.To evaluate thermal stability and higher heating values,Thermogravimetric Analysis(TGA),Differential Scanning Calorimetry(DSC),and bomb calorimetry were performed.The chemical analysis revealed that bagasse contained 50.6%cellulose and 21.6%lignin,kenaf bast fibers had 58.5%cellulose and 10%lignin,and cotton stalks exhibited 40.3%cellulose and 21.3%lignin.The FTIR curves demonstrated a notable similarity among the fibers.The TGA analysis showed degradation temperatures of 321°C for bagasse,354°C for kenaf bast fibers,and 289°C for cotton stalks.The DSC analysis revealed glass transition temperatures of 81°C for bagasse,66.3°C for cotton stalks,and 64.5°C for kenaf bast fibers.The higher heating values were measured as 17.3,16.6 and 17.1 MJ/kg for bagasse,kenaf bast fibers,and cotton stalks,respectively.The three fibers have a high potential for biocomposites and bioenergy material manufacturing.
文摘In this paper, we deals with mechanical performance of resin impregnation with natural fiber and fiber reinforced composites. The effect of the addition of a rein impregnation process on static strength of the injection molded composites was investigated by carrying out tensile and banding tests, followed by Scanning electron microscopy (SEM) observation of fiber surface and fracture surface of composites. The tensile strength of natural fiber and natural fiber reinforced composites with resin impregnation method increases with Polyvinyl alcohol (PVA) impregnation. In addition, Phenol resin impregnation recovers fiber tensile strength after alkali treatment. Resin impregnation causes decrease in contact surface area;however, it does not cause decrease in mechanical properties. Our results suggest that the using rein impregnation method has better effect on the mechanical properties of natural fiber reinforced Polypropylene (PP) composites.
文摘The experimental results showed that the duration of microbial retting processing of kenaf fibers by using aerobic microbe was four times shorter than that by using anaerobic microbe. The residual gum percentage,breaking strength, breaking elongation and linear density of aerobic retted kenaf bundle fibers did not show significantly difference with that of anaerobic retted kenaf bundle fibers by ANOVA-Tukey's studentized test at a = 5% except for the softness. The bioenergetic principle and the calculation of the amount of ATP produced during the decomposition processing of kenaf gums were used to explain why the retting duration in the case of using aerobic microbes was much shorter than that of using anaerobic microbes.
文摘This paper deals with the chemical treatment of kenaf fi-ber and the spinning of the kenaf yarn blended with cot-ton. The experimental results show that after being treated by alkli, the properties of kenaf fiber have im-proved obviously, which made it possible to produce the yarn of kenaf blended with cotton. The results are very helpful for the utilization of kenaf fiber.
文摘为探寻适合红麻纤维蒸气爆破预处理与酶解糖化的技术参数,开展红麻纤维气爆压力、保压时间、填料量等蒸气爆破预处理技术参数研究,并对蒸气爆破预处理后的红麻纤维进行浴比、酶解时间、酶种类、酶配比、酶用量等酶解糖化单因子试验与正交试验。结果表明:红麻纤维气爆预处理以填料量100%、气爆压力2.5 MPa、保压时间240~300 s的效果较好;红麻纤维酶解糖化的较优工艺参数为浴比(1∶5.00)^(1∶7.50),纤维素酶和木聚糖酶的配比2∶3,采用混合酶(1.50%纤维素酶+2.250%木聚糖酶),p H 5.0,糖化率可达70%以上。