Wearability is one of important factors for the textile product quality. The wearability of bamboo pulp knitted fabrics was mainly discussed which were treated with chitosan and cupper ammonia solution. Tensile and bu...Wearability is one of important factors for the textile product quality. The wearability of bamboo pulp knitted fabrics was mainly discussed which were treated with chitosan and cupper ammonia solution. Tensile and bursting properties, abrasion resistance,drapability,air permeability,moisture-penetrability and warmth retention properties of fabrics were tested to investigate the changes. The results showed that chitosan pretreatment improved the tensile and bursting strengths,abrasion resistance and moisture penetrability,but decreased the drapability and air permeability.Copper ammonia solution treatments decreased the tensile and bursting strengths,abrasion resistance and air permeability,but increased the drapability, moisture penetrability and warmth retention properties.展开更多
Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually prese...Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.展开更多
The oxidized bamboo pulp fiber yarns were prepared by the HNO3?/H3PO4-NaNO2 oxidation system. The effects of the oxidation concentration and reaction time on the weight loss, the carboxyl content and the breaking stre...The oxidized bamboo pulp fiber yarns were prepared by the HNO3?/H3PO4-NaNO2 oxidation system. The effects of the oxidation concentration and reaction time on the weight loss, the carboxyl content and the breaking strength of the bamboo pulp fiber yarns were studied and the aggregation structure was investigated by Fourier transform infrared, X-ray and scanning electron microscopy. The results revealed an increase in carboxyl content and a decrease in breaking strength of oxidized bamboo pulp fiber yarns with increasing concentration of oxidant and reaction time. The breaking strength of oxidized bamboo fiber yarns was damaged seriously once the reaction time was more than 120 min or the concentration of oxidant was greater than 1.0%. The crystallinity of bamboo pulp fibers increased slightly under low oxidation degree but decreased with higher oxidation degree.展开更多
Bamboo was used as raw material for unbleached pulp production.An acetic acid prehydrolysis process was employed before the pulping process.The effect of acetic acid prehydrolysis on pulp properties was investigated.T...Bamboo was used as raw material for unbleached pulp production.An acetic acid prehydrolysis process was employed before the pulping process.The effect of acetic acid prehydrolysis on pulp properties was investigated.The results showed that some components,such as hemicellulose and extractives,were degraded or dissolved in the prehydrolysis process prior to kraft pulping.SEM images of the substrate after treatment indicated that the parenchyma cell wall was thinner,and the size of pores between fiber bundle cell walls was larger.The pulping results showed that acetic acid prehydrolysis could improve the pulp quality and make the pulp easier to bleach.The brightness of the pulp reached 59.6%ISO with a single oxygen delignification step.The acetic acid prehydrolysis decreased pulp viscosity and fiber length,but not significantly.The amount of parenchyma cells in the pulp was reduced,which was beneficial for papermaking and improving mechanical strength of paper.This procedure has good potential for unbleached pulp production.展开更多
In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by ...In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by nano CaCO_(3)blending(BM)and impregnation modification(IM)technology.The composites were produced using hot press(HPMP),extrusion(EMP)and injection molding process(IMP).The physical morphology of BPF was similar at different manufacturing processes.Compared to the samples manufactured by HPMP,a decrease in the(specific)flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO_(3)manufactured by EMP and IMP were observed.The injection molded composites exhibited the best values in the(specific)impact strength,(specific)tensile properties.IM had a greater effect on the rheological behavior of the composites than BM,and nano CaCO_(3)treatment most effectively affected the performance of the extrusion molded composites.展开更多
By applying ultrasound at different stage of kraft pulping process, the properties of kraft pulp produced by ultrasonic treatment were studied and compared with those by conventional method. The results indicated that...By applying ultrasound at different stage of kraft pulping process, the properties of kraft pulp produced by ultrasonic treatment were studied and compared with those by conventional method. The results indicated that, while the performances of the pulp were close to conventional kraft pulp, the chemical-to-wood ratio decreased from 20% to 17.5%, cooking time was shortened from 140 to 120 rain, and the yield increased. When the ultrasound came into play at the 90th minute during pulping process, the properties of the produced bamboo fiber were the most desirable.展开更多
We investigated the effects of supercritical ammonia on pulping of bamboo in a preliminary study,using testers such as differential scanning calorimetry(DSC),scanning electron microscopy(SEM),X-ray diffraction(XR...We investigated the effects of supercritical ammonia on pulping of bamboo in a preliminary study,using testers such as differential scanning calorimetry(DSC),scanning electron microscopy(SEM),X-ray diffraction(XRD) and energy dispersive spectroscopy(EDS).The results indicate that under supercritical conditions at 185-190°C,it is possible for the ammonia to realize bamboo pulping.Compared with conventional kraft pulping,the products can meet the quality requirements of industrial paper.展开更多
Refining of pulp significantly contributes to papermaking process by affecting the runnability of the stock and quality of end product. The greater the production rates of a paper, the greater are the effects of machi...Refining of pulp significantly contributes to papermaking process by affecting the runnability of the stock and quality of end product. The greater the production rates of a paper, the greater are the effects of machine downtime through breaks. A correct approach towards refining treatment is very essential for energy savings and product with desired properties. Papermakers are being encouraged to use non-wood fibres for a variety of reasons - the environment, changing agricultural policy and long-term fibre supply. Compared with wood fibres, there is less knowledge on how to treat non-wood fibres for optimum performance. Laboratory studies aimed at understanding the behaviour of unbleached bamboo long fibre fraction pulp on refining in Escher Wyss Laborefiner under simulated process conditions included investigations of the important parameters like wet web tensile, wet web elongation, water retention value and paper strength properties. The paper describes the influence of two specific edge loads, 1000 and 1500 Ws/km on refining of pulp. Bamboo long fibre fraction pulp responds better to lower intensity refining to develop pulp strength.展开更多
The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO...The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO4 in P stage were optimized. The results indicated that good results of chlorine dioxide bleaching were obtained under the conditions of ClO2 2.0%,pH 4, and the highest final brightness(86.4%ISO) and the lowest final Kappa number(1.37) were attained when the charge of EDTA in Q stage was 0.4%, charge of MgSO4 in P stage was 0.2%, and the other conditions of P stage : pulp consistency 10%, H2O2 charge 2.5%, NaOH charge 1.4%, temperature 90℃ and time 120 min. A comparison of bleaching results, pulp strength and effluent characteristics of bamboo kraft pulp between DQP and CEH sequences was done. The results indicated that bamboo kraft pulp could be bleached to brightness of above 83%ISO by both DQP and CEH sequences. Compared with CEH bleached pulp, DQP bleached pulp had slightly lower brightness, better brightness stability, higher pulp viscosity, better strength properties and lower pollution loads.展开更多
Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed...Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed by the methods of Analysis of variance and correlation coefficient to reveal the geographic genetic variation situation. The results showed that there are significant differences be- tween fiber length, fibrin and 1% NaOH extraction contents of B. chungii from 8 provenances; moreover, the fiber length and fiber length/width ratio had a decreasing change pattern with geographic variation from the south to the north in altitude (from high to low in ele- vation). The heritabilities for fibrin, fiber length, 1% NaOH extractive, lignin and fiber length/width ratio were 0.7, 0.84, 0.54, 0.38 and 0.13, respectively. A significant negative correlation was found between 1% NaOH extraction, benzo-alcohol extraction contents and bamboo culm yield, whereas there was a significant positive correlation between fibrin contents and bamboo wood yield. Besides, a close correlation was detected between fiber dimensions indices and bamboo growth or bamboo wood yield. Finally, three provenances with high qualities and culm yield, i.e. Huaiji, Xinyi and Guilin, were selected as superior sources based on principal component analysis.展开更多
文摘Wearability is one of important factors for the textile product quality. The wearability of bamboo pulp knitted fabrics was mainly discussed which were treated with chitosan and cupper ammonia solution. Tensile and bursting properties, abrasion resistance,drapability,air permeability,moisture-penetrability and warmth retention properties of fabrics were tested to investigate the changes. The results showed that chitosan pretreatment improved the tensile and bursting strengths,abrasion resistance and moisture penetrability,but decreased the drapability and air permeability.Copper ammonia solution treatments decreased the tensile and bursting strengths,abrasion resistance and air permeability,but increased the drapability, moisture penetrability and warmth retention properties.
基金the National Key Research and Development Program of China(2017YFB0307900,2019YFC1905903)the National Natural Science Foundation of China(31700507)the Major Project on the Integration of Industry-Education-Research of Fujian Provincial Department of Science and Technology(2018H6003).
文摘Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.
文摘The oxidized bamboo pulp fiber yarns were prepared by the HNO3?/H3PO4-NaNO2 oxidation system. The effects of the oxidation concentration and reaction time on the weight loss, the carboxyl content and the breaking strength of the bamboo pulp fiber yarns were studied and the aggregation structure was investigated by Fourier transform infrared, X-ray and scanning electron microscopy. The results revealed an increase in carboxyl content and a decrease in breaking strength of oxidized bamboo pulp fiber yarns with increasing concentration of oxidant and reaction time. The breaking strength of oxidized bamboo fiber yarns was damaged seriously once the reaction time was more than 120 min or the concentration of oxidant was greater than 1.0%. The crystallinity of bamboo pulp fibers increased slightly under low oxidation degree but decreased with higher oxidation degree.
基金financial support from the National Natural Science Foundation of China (31570569)
文摘Bamboo was used as raw material for unbleached pulp production.An acetic acid prehydrolysis process was employed before the pulping process.The effect of acetic acid prehydrolysis on pulp properties was investigated.The results showed that some components,such as hemicellulose and extractives,were degraded or dissolved in the prehydrolysis process prior to kraft pulping.SEM images of the substrate after treatment indicated that the parenchyma cell wall was thinner,and the size of pores between fiber bundle cell walls was larger.The pulping results showed that acetic acid prehydrolysis could improve the pulp quality and make the pulp easier to bleach.The brightness of the pulp reached 59.6%ISO with a single oxygen delignification step.The acetic acid prehydrolysis decreased pulp viscosity and fiber length,but not significantly.The amount of parenchyma cells in the pulp was reduced,which was beneficial for papermaking and improving mechanical strength of paper.This procedure has good potential for unbleached pulp production.
基金This study is financially supported by the Basic Research Operating Expenses Program of International Centre for Bamboo and Rattan(1632021002).
文摘In order to investigate the effect of the relative motion of nano CaCO_(3)reinforced bamboo pulp fiber(BPF)/HDPE composite components on the mechanical performance,a comparative study was performed.BPF was treated by nano CaCO_(3)blending(BM)and impregnation modification(IM)technology.The composites were produced using hot press(HPMP),extrusion(EMP)and injection molding process(IMP).The physical morphology of BPF was similar at different manufacturing processes.Compared to the samples manufactured by HPMP,a decrease in the(specific)flexural strength of BPF/HDPE composites and an increase in those of composites treated by nano CaCO_(3)manufactured by EMP and IMP were observed.The injection molded composites exhibited the best values in the(specific)impact strength,(specific)tensile properties.IM had a greater effect on the rheological behavior of the composites than BM,and nano CaCO_(3)treatment most effectively affected the performance of the extrusion molded composites.
文摘By applying ultrasound at different stage of kraft pulping process, the properties of kraft pulp produced by ultrasonic treatment were studied and compared with those by conventional method. The results indicated that, while the performances of the pulp were close to conventional kraft pulp, the chemical-to-wood ratio decreased from 20% to 17.5%, cooking time was shortened from 140 to 120 rain, and the yield increased. When the ultrasound came into play at the 90th minute during pulping process, the properties of the produced bamboo fiber were the most desirable.
文摘We investigated the effects of supercritical ammonia on pulping of bamboo in a preliminary study,using testers such as differential scanning calorimetry(DSC),scanning electron microscopy(SEM),X-ray diffraction(XRD) and energy dispersive spectroscopy(EDS).The results indicate that under supercritical conditions at 185-190°C,it is possible for the ammonia to realize bamboo pulping.Compared with conventional kraft pulping,the products can meet the quality requirements of industrial paper.
文摘Refining of pulp significantly contributes to papermaking process by affecting the runnability of the stock and quality of end product. The greater the production rates of a paper, the greater are the effects of machine downtime through breaks. A correct approach towards refining treatment is very essential for energy savings and product with desired properties. Papermakers are being encouraged to use non-wood fibres for a variety of reasons - the environment, changing agricultural policy and long-term fibre supply. Compared with wood fibres, there is less knowledge on how to treat non-wood fibres for optimum performance. Laboratory studies aimed at understanding the behaviour of unbleached bamboo long fibre fraction pulp on refining in Escher Wyss Laborefiner under simulated process conditions included investigations of the important parameters like wet web tensile, wet web elongation, water retention value and paper strength properties. The paper describes the influence of two specific edge loads, 1000 and 1500 Ws/km on refining of pulp. Bamboo long fibre fraction pulp responds better to lower intensity refining to develop pulp strength.
文摘The influential factors of DQP bleaching, chlorine dioxide bleaching, chelation and hydrogen peroxide bleaching, of bamboo kraft pulp were studied. The pH value in D stage, dosage of EDTA in Q stage and charge of MgSO4 in P stage were optimized. The results indicated that good results of chlorine dioxide bleaching were obtained under the conditions of ClO2 2.0%,pH 4, and the highest final brightness(86.4%ISO) and the lowest final Kappa number(1.37) were attained when the charge of EDTA in Q stage was 0.4%, charge of MgSO4 in P stage was 0.2%, and the other conditions of P stage : pulp consistency 10%, H2O2 charge 2.5%, NaOH charge 1.4%, temperature 90℃ and time 120 min. A comparison of bleaching results, pulp strength and effluent characteristics of bamboo kraft pulp between DQP and CEH sequences was done. The results indicated that bamboo kraft pulp could be bleached to brightness of above 83%ISO by both DQP and CEH sequences. Compared with CEH bleached pulp, DQP bleached pulp had slightly lower brightness, better brightness stability, higher pulp viscosity, better strength properties and lower pollution loads.
文摘Using 3-year-old culms of 8 provenances of Bambusa chungii from Guangdong, Guangxi and Hainan Provinces, the indexes of wood properties, such as fiber dimensions and chemical composition were investigated and analyzed by the methods of Analysis of variance and correlation coefficient to reveal the geographic genetic variation situation. The results showed that there are significant differences be- tween fiber length, fibrin and 1% NaOH extraction contents of B. chungii from 8 provenances; moreover, the fiber length and fiber length/width ratio had a decreasing change pattern with geographic variation from the south to the north in altitude (from high to low in ele- vation). The heritabilities for fibrin, fiber length, 1% NaOH extractive, lignin and fiber length/width ratio were 0.7, 0.84, 0.54, 0.38 and 0.13, respectively. A significant negative correlation was found between 1% NaOH extraction, benzo-alcohol extraction contents and bamboo culm yield, whereas there was a significant positive correlation between fibrin contents and bamboo wood yield. Besides, a close correlation was detected between fiber dimensions indices and bamboo growth or bamboo wood yield. Finally, three provenances with high qualities and culm yield, i.e. Huaiji, Xinyi and Guilin, were selected as superior sources based on principal component analysis.