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1.
The mechanism of rosin size retention in rosin soap size-alum systems was studied on the basis of sizing behavior and the rosin size and aluminum contents of handsheets prepared under normal and particular conditions. Rosin size, aluminum, and calcium contents of handsheets prepared with various stirring times of pulp suspensions after pH adjustment suggested that rosin size components adsorbed on pulp fibers predominantly have the structure of free rosin acid rather than rosin aluminum or calcium salt. When a carboxyl group-blocked pulp was used, the rosin size content clearly decreased. This result shows that pulp carboxyl groups play a significant role in rosin size retention. Electrostatic interactions between dissociated carboxyl groups of pulps and anionic rosin size components through cationic aluminum compounds must be present in pulp suspensions. On the other hand, nonionic interactions in pulp suspensions, which occur particularly around pH 6.2–6.5, may also contribute to rosin size retention and appearance of sizing features. When the carboxyl group blocked pulp was used, some rosin size components were retained in the handsheets in largely coagulated form, resulting in no or quite low sizing levels, when the handsheets were dried at 20°C.This research was presented in part at the 64th pulp and paper research conference of Japan TAPPI, Tokyo, June 1997 相似文献
2.
Retention behavior of size and aluminum components in handsheets prepared in rosin soap size-alum systems 总被引：2，自引：0，他引：2
Handsheets were prepared with rosin soap size and aluminum sulfate under various conditions, and the retention behavior of the rosin size and aluminum components in the handsheets was studied. Pyrolysis-gas chromatography and X-ray fluorescence analysis were used to determine the size and aluminum contents in the handsheets, respectively. When the addition level of rosin soap size varied from 0% to 4% and that of aluminum sulfate was fixed at 2%, the rosin size content increased with the increase in the size addition level, whereas aluminum and calcium contents were roughly constant. Under these conditions, handsheets prepared from fines-free pulp had aluminum contents less than those for the original beaten pulp, probably because the former pulp had a carboxyl content less than that of the latter pulp. Not only the conventional rosin retention mechanism but also mechanism proposed below must exist in the rosin soap size-alum systems. That is, some aluminum compounds originating from aluminum sulfate are adsorbed on pulp fibers immediately after the aluminum sulfate addition. These adsorbed aluminum compounds form cationic sites on pulp fibers, and free rosin acid components with anionic charges are then adsorbed onto the cationic sites of pulp fibers at the wet-end.This research was presented in part at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 1996 相似文献
3.
Handsheets were prepared with aluminum sulfate under various conditions of pulp suspension, and factors influencing retention behavior of aluminum components on the handsheets were studied on the basis of their aluminum contents. When deionized water was used in the handsheet-making process, aluminum contents in the handsheets had a plateau level of 0.7mg/g in the range of 1%–8% Al2(SO4)3 addition levels on dry weight of pulp. On the other hand, when tap water was used aluminum contents increased up to 5.6 mg/g, increasing the Al2(SO4)3 addition levels to 8%. The high aluminum contents in the handsheets are explained in terms of pH and the presence of calcium ions from the tap water used. Cationic aluminum species, which are formed from aluminum sulfate added to pulp suspensions, are primarily adsorbed on pulp fibers by electrostatic interactions with carboxyl groups in the pulp, competing with OH– ions in water. These aluminum components, once adsorbed on pulp fibers by ionic interactions, are not removed from the fibers by extending the stirring time of the pulp suspensions.This research was presented in part at the 48th annual meeting of the Japan Wood Research Society in Shizuoka, April 1998 相似文献
4.
Retention behavior of size and aluminum components on handsheets in rosin-ester size/alum systems 总被引：1，自引：0，他引：1
Anionic emulsion sizes consisting of rosin triglyceride esters and partly fortified rosin acids (i.e., rosin-ester sizes), have recently been used as internal sizes for alkaline papermaking. In this study, handsheets were prepared from pulp suspensions with alum and a rosin-ester size under various conditions, and sizing degree and size and aluminum contents of the handsheets were determined. Aluminum compounds originating from alum added to the pulp suspensions behave as retention aids of the rosin-ester size even in alkaline papermaking under limited conditions. Carboxyl groups in pulp are the primary retention sites of aluminum compounds in pulp suspensions. They form cationic sites on pulp fibers, and thus the anionic size emulsion particles are adsorbed on pulp fibers by electrostatic interactions. However, the cationic charges of aluminum compounds on pulp fibers decrease and finally disappear completely with the lapse of time after the alum addition by forming ionic bonds between the cationic sites and OH– ions. Thus, pH values of the pulp suspensions and timing of the size addition strongly influence the retention values of the rosin-ester size and the resultant sizing features.This research was presented in part at the 1995 autumn meetings of the Society of Fiber Science and Technology Japan in Hamamatsu, October 1995 相似文献
5.
Interactions between pulp fibers and aluminum compounds in pulp suspensions were studied using fibrous cellulose (FC) and fibrous carboxymethylcellulose (FCMC) powders as models of pulp fibers by X-ray fluorescence analysis and27Al nuclear magnetic resonance. When deionized water was used at pH 4–5, water-soluble cationic aluminum species (Al3+, aluminum oligomer, and polyaluminum species) were adsorbed on the solid FCMC, forming carboxylic acid aluminum salts by cation exchange. The formation of these nondissociated pulp-COOAl type structures in paper sheets may contribute to some decreases in hydrophilic property. On the other hand, the water-soluble cationic aluminum species had nearly no interactions with hydroxyl groups of solid cellulose in the suspensions at pH 4–5. When tap water was used at pH 5–7, some aluminum components were retained on not only FCMC but also the FC sample. Probably, water-insoluble Al(OH)3 flocs are formed in the suspensions at pH 5–7 and retained on the FC sample by simple filtration effect. Therefore, two mechanisms of the aluminum retention (i.e., electrostatic interactions and a simple filtration effect) may exist between pulp fibers and aluminum components in the practical papermaking process.This research was presented in part at the 5th annual meeting of the Japan Cellulose Society, Kyoto, July 1998 相似文献
6.
The distribution of aluminum components in cross sections of pulp fibers for alum-treated handsheets was successfully measured by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. In this case, gas-phase osmium coating of paper samples is necessary for the samples to have improved stability to long-term irradiation by electron beams at high magnification during the SEM-EDX measurements. The EDX line-analysis method was superior to the elemental mapping image method in the quantification of aluminum components. According to the SEM-EDX measurement for handsheets prepared from a pulp suspension by adding 2% (on dry weight of pulp) aluminum sulfate, the aluminum components were distributed almost homogeneously in the cross sections of pulp fibers. Aluminum species with smaller sizes than those of A1(OH)3 flocs could probably penetrate the pulp fibers. Thus, aluminum components present only at the pulp fiber surfaces may contribute to retention of colloidal substances in pulp suspensions. From this aspect, a large amount of aluminum components present in the inside pulp fibers may be wasted.This report was presented at the 49th annual meeting of the Japan Wood Research Society at Tokyo, April 1997 相似文献
7.
Various aluminum compounds were added to pulp suspensions, and the adsorption behavior of their aluminum components on pulp fibers was studied. Aluminum contents in the handsheets were determined using an energy dispersive X-ray analyzer attached to a scanning electron microscope and an X-ray fluorescence analyzer. Although aluminum contents in the handsheets increased with increasing additions of the aluminum compounds, the detailed adsorption patterns varied among the aluminum compounds used. Their chemical structures and the pH values of the pulp suspensions greatly influence the adsorption behavior. When fines are present in the pulp suspensions, the aluminum components are predominantly adsorbed on the fines, probably due to their larger surface areas or the higher carboxyl contents compared to those of coarse fibers. Not only aluminum flocs but also far smaller components such as various aluminum cations seemed to be adsorbed on pulp fibers. Most aluminum flocs, which are formed in pulp suspensions by reacting with OH and entrapped in a fiber matrix by filtration effects, are removable by repeated mechanical agitation of the pulp suspensions. 相似文献
8.
Simon Potter Sandra Reath Ashif Hussein Wai Gee Val Lawrence James Drummond 《Wood Science and Technology》2003,37(3-4):321-329
We have found that kraft pulp handsheets, made from a number of hybrid poplar (Populus trichocarpa × Populus deltoides) clones, contain unusual surface deformations caused by vessel element mineral blockages. The blockages were composed mainly of calcium salt deposits that survived chemical pulping and beating processes. Our findings confirm that a natural process of accumulation of calcium salts occurs in certain poplar species. In this article, we describe the implications for the multi-use implementation of these poplars in short-rotation, intensive-culture plantations. 相似文献
9.
Application of cationic polymer prepared from sulfuric acid lignin as a retention aid for usual rosin sizes to neutral papermaking 总被引：3，自引：0，他引：3
Cationic polymers that acted as the retention aids for usual rosin sizes in neutral papermaking were prepared from sulfuric acid lignin (SAL), one type of acid lignin. To convert SAL to the cationic polymer (MP-SAL), SAL was phenolated and then treated by the Mannich reaction to introduce the amino groups. In the MP-SAL single system, MP-SAL exhibited high sizing effectiveness in neutral papermaking with the rosin emulsion size. However, MP-SAL showed no sizing effectiveness when soap rosin size was used. MP-SAL showed increased sizing effectiveness as the pK
a of the introduced amino group increased. From this and comparison of the sizing degrees of MP-SAL and polyethylenimine, which possesses a linear structure, it was suggested that the sizing effectiveness was not only affected by the charge density and molecular weight, but also by the basicity of the introduced amino groups and the molecular structure of the retention aid. In the alum–MP-SAL dual system, alum and MP-SAL synergistically enhanced the sizing effectiveness in the rosin emulsion sizing at neutral pH. In turn, this allowed a decrease in the MP-SAL dosage and resulted in a small decrease in brightness.Part of this report was presented at the 48th Lignin Symposium, October 2003, Fukui 相似文献
10.
Fiber charge characteristics of pulp suspensions containing aluminum sulfate were investigated with relation to adsorption behavior of aluminum components on the pulp fibers by streaming potential measurement using a particle charge detector, X-ray photoelectron spectroscopy, and X-ray fluorescence analysis. When aluminum sulfate was added to a pulp suspension prepared using deionized water, a streaming potential of the suspension went from negative to slightly negative according to the adsorption of aluminum components on the pulp fibers. Subsequent addition of a dilute NaOH solution to the suspension drastically cationized the fibers in the pH range of around 5 by predominant and homogeneous adsorption of cationic aluminum complexes on the fiber surfaces. However, the aluminum flocs that formed heterogeneously on the fiber surfaces at higher pH by further alkali addition made nearly no contribution to cationization of the fibers, although the abundant aluminum components were retained in the pulp sheets. Therefore, only aluminum cations adsorbed uniformly on the fiber surfaces perform well to control the charge properties of the pulp fibers at the wet end; and the preferential aluminum adsorption behavior on the fiber surfaces, by utilizing the required amounts of hydroxyl ions, probably accounts for the effective cationization of the fibers under acidic to neutral papermaking conditions.This research was presented in part at the presymposium of the International Symposium on Wood and Pulping Chemistry, Seoul, June 1999; at the International Symposium on Environmentally Friendly and Emerging Technologies for a Sustainable Pulp and Paper Industry, Taipei, April 2000; and at the 2000 annual meeting of the Society of Fiber Science and Technology, Japan, Kyoto, June 2000 相似文献
11.
去氢枞酸为原料表面活性剂的合成及性能研究 总被引：11，自引：2，他引：9
从歧化松香中分离提纯出去氢枞酸。以去氢枞酸为原料合成了２－羟基－３－［Ｎ－（３－去氢枞酰氧基－２－羟基）丙基－Ｎ－羟乙基］氨基丙磺酸钠和２－羟基－３－［Ｎ－（３－去氢枞酰氧基－２－羟基）丙基－Ｎ－乙基］氨基丙磺酸钠这两种未见文献报道的表面活性剂，产品的结构通过紫外光谱、红外光谱和核磁共振氢谱进行了鉴定，测定了这两种表面活性剂的最低溶解温度、临界胶束浓度、钙皂分散力和钙离子稳定性。 相似文献
12.
13.
An elemental chlorine-free (ECF)-bleached soft-wood kraft pulp was treated first with a carboxymethyl cellulose (CMC, degree
of substitution 0.3, 1% on pulp) and then with alkyltrimethylammonium bromides (alkyl chain lengths of C10 to C16). Surprisingly, the treatment with dodecyltrimethylammonium bromide (C12TAB) markedly increased the internal and tensile strengths of the handsheets prepared from the modified pulp. Environmental
scanning electron microscopy (ESEM) showed that these properties could be partly explained by the “rope/gum-like” bridges
that were formed between the fibers. 相似文献
14.
Katsuhiro Tokugawa Dan Aoki Ryutaro Asai Yasuyuki Matsushita Masao Ishiguro Yasufumi Noda Kazuhiko Fukushima 《Journal of Wood Science》2017,63(3):281-287
In order to understand the kraft pulp decolouring mechanism on using a nonionic detergent, the pulp washing process and the resulting pulp handsheets were investigated by examining the brightness, kappa number, thioacidolysis product yield, and dewatering efficiency in the pressing sheet making process. The pulp decolouring could be attributed to a decrease in the lignin content and an improvement in the dewatering efficiency. Furthermore, the detergent distribution in the aqueous pulp suspension obtained during the pulp washing process was visualised using cryo-time-of-flight secondary ion mass spectrometry/scanning electron microscopy (cryo-TOF-SIMS/SEM). The detergent was clearly observed at the transverse surface of the pulp fibre cell wall and was also detected in the lumen of the fibres, suggesting the permeation of the detergent into the pulp fibre cell wall. Based on these results, the pulp decolouring mechanism can be proposed as follows: the detergent permeates into the pulp fibre cell wall and promotes the solution-exchange between the inside and the outside parts of the fibre cell wall, finally washing away the chromophoric substances such as lignin and its degradation products owing to the enhanced dewatering efficiency. 相似文献
15.
Paper density, tensile index, sizing degree, and other properties of the handsheets were measured in term of addition level of bulking promoters and alkyl ketene dimer (AKD). Bulking promoters had clear bulking effects, and in subsequent addition of the AKD, the sheet density was further decreased slightly. Although the density of the handsheet decreased from 0.64 to 0.61 g/cm3 when 0.2% AKD was added with the 0.8% bulking promoter, tensile strength decreased from 20.3 to 19.8 Nm/g. The addition of AKD led to suppression of the decrease in the tensile index. The bulking promoter may also have potential to give sizing effects to the paper sheet as well as the increase in paper thickness. When 0.05% AKD was added together with 0.8% of bulking promoter, the sizing degree of the handsheet was 25.6 seconds, and it was almost the same, 27.3 seconds, as the addition of 0.1% AKD only. AKD retention in the handsheet was determined by pyrolysis-gas chromatography (Py-GC). The addition of the bulking promoter contributed to AKD retention in the handsheet regardless of the sizing degree. Wetting characteristics of the handsheet were determined by contact angle measurements. Surface free energy, γ s , of the handsheet as calculated from the contact angle decreased as the level of AKD addition increased. 相似文献
16.
As a continuing study of six organic solventsoluble lipophilic extractives and one water-soluble lipophilic extract from wheat straw, seven extracts were further compared using Fourier transform-infrared (FT-IR) analysis,1H and13C nuclear magnetic resonance (NMR) spectroscopy, and thermal analysis. In the FT-IR spectra of two-thirds chloroform/one-third methanol, methyltertbutyl ether (MTBE), hexane, petroleum ether, and dichloromethane extracts, a strong band at 1746cm–1 is indicative of the ester carbonyl of triglycerides or steryl esters or waxes, whereas the occurrence of carboxylic carbonyl of free fatty acids or resin acids at 1712–1719 cm–1 is verified in the spectra of two-thirds toluene/one-third ethanol and hot water extracts. Signals at 187.9,178.4, and 173.3 ppm in the13C NMR spectrum of MTBE extract correspond to carbonyl groups of resin acids, fatty acids, and fatty acid/steryl esters, respectively. All the extractives were to varying degrees thermally unstable at a temperature of about 200°C, and the melting temperature occurred at about 54°C. 相似文献
17.
以妥尔油脂肪酸二聚酸为原料,先与聚乙二醇(PEG 400)缩聚后得到聚酯,然后再用松香对聚酯封端,制备了松香基聚酯醚型非离子高分子表面活性剂,并对其性能进行了研究。聚酯适宜的制备工艺条件:减压条件下,反应物二聚酸与聚乙二醇的摩尔比为1∶1.20,催化剂SnC l2用量为二聚酸质量的0.30%,反应温度200℃,反应时间6 h,酯化率达到98.11%。产物的数均相对分子质量(Mn)6 135,重均相对分子质量(Mw)7 438,相对分子质量分布系数(Mw/Mn)为1.212且呈好的窄分布状态。正交试验优化后的松香封端反应的条件为:再补加聚酯质量0.20%的催化剂SnC l2,聚酯与松香物质的量之比为1∶1.30,反应温度215℃,反应时间2.8 h,封端率达62.75%。红外光谱验证了目标产物的存在。性能研究表明,产物具有很好的钙皂分散力、消泡和抑泡力、乳化性和乳化稳定性。 相似文献
18.
Cationized pulp fibers （CPF） were prepared by the adsorption of a novel biodegradable cationic ester quaternary ammonium salt （31441） on bleached softwood kraft pulp fibers. The optimized conditions for the CPF preparation were： 4% of 31441 （based on oven-dry pulp）, 80℃ and 30 rain. The CPF was characterized by FT-IR, SEM and XPS. Experimental results showed that the CPF improved the retention of precipitated calcium carbonate （PCC） filler significantly. With 0.9% CPF （based on oven-dry pulp）, the retention of PCC increased from 57.53% to 72.21%. The physical properties of paper were also slightly improved. The tensile strength and burst strength of the paper with CPF were higher than those with CPAM. CPF addition had no effect on the stock drainage. 相似文献
19.
《Wood material science & engineering》2013,8(3-4):154-166
Abstract Acetic–fatty esters of Scots pine sawdust (SPS) were obtained by reaction of SPS with mixtures containing acetic–fatty anhydrides and no solvent or catalyst. Such mixtures were synthesized by reaction between a carboxylic acid and acetic anhydride. The global reaction of acetic anhydride and a fatty acid yields at equilibrium a mixture of five compounds: acetic–fatty anhydride, acetic anhydride, fatty acid, acetic acid and fatty anhydride. The influence of temperature, molar ratio, reaction time and length of the fatty chain on the esterification and on the ratio of grafted acetyl/fatty acyl was investigated. Static contact angles (CAs) with water were measured over 5 min. CA values were dependent on the fatty acyl content and independent of the acetyl content. The minimum ester content of the oleoyl group required to obtain permanent water repellency was 25 mmol kg?1. Water vapour adsorption measurements indicated that in contrast to water repellency, hydrophobicity to water vapour was correlated with the total mass acyl content. 相似文献
20.
David J. Simbo Sebastiaan De Smedt Nina Van den Bilcke Bruno De Meulenaer John Van Camp Veronique Uytterhoeven Filip Tack Roeland Samson 《Agroforestry Systems》2013,87(3):493-505
Among the priority species identified for domestication in the Sahel region of Sub-Sahara Africa is the baobab (Adansonia digitata L.) tree. The quantification of the variation in nutrient content and fruit morphological traits of trees is one of the most important steps in identifying superior planting material for domestication. Ten provenances in Mali covering all the different agro-ecological zones were selected and the fruit morphological traits, vitamin C, calcium, iron and colour were studied. Mean pulp content was 2,149 ± 1,117 , 2,406 ± 776 and 25 ± 17 mg kg?1 for vitamin C, calcium and iron, respectively. Fruit pulp colour varied from white, creamy to pink and a significant correlation between pulp vitamin C content and reflectance in the green and blue bands was observed. Significant negative correlations were found between rainfall and pulp vitamin C content and between mean annual temperature and fruit and pulp weight and pulp fraction, suggesting that these traits are influenced by the environment. Pulp iron content correlated positively with topsoil sodicity and base saturation. Similarly, pulp vitamin C content correlated positively with topsoil sand fraction. Pulp reflectance in the blue and green bands correlated negatively with topsoil pH water and base saturation, respectively. The variation in nutritive and morphological traits offers the opportunity for selecting plus trees with a combination of desired traits for domestication. 相似文献