造纸化学品述评

填料在纸浆纤维的水悬浮液中加填料一般都是为了增加纸张的亮度、平滑度、不透明度和吸墨性能。在书籍纸张中添加填料的主要目的是增加纸张的柔韧性。为取得这种效果,需要使用各种类型的填料。填料的种类和混合的比例则需根据使用要求和经济效益确     

沉淀法白炭黑粉末的制法

本发明涉及白炭黑粉末的制造方法。这种白炭黑粉末可用作纸张填料、塑料和橡胶等的填充剂，以及药品等的载体等等。 白炭黑通常是由直径数十纳米的一次粒子聚集而成的数百纳米到数百微米的微粒，由于其吸油性很强，被广泛用作纸张填料、塑料和橡胶等的填充剂、农药等药品的载体，以及用于其它各种目的。     

提升纸张强度的近期研究进展

对各种提升纸张强度的方法进行了总结,主要包含添加无机填料、浆内添加高分子、表面施胶、表面溶解、纳米纤维涂层等方法,并尝试解释了各种方法的增强机理,讨论了各种方法的优缺点,目的是为制造新型高强纸张提供思路。     

废纸回收利用中存在的问题

世界各国都十分重视废纸回收利用,尤其在一些工业发达国家,例如美国,采用法律的形式严格限定了纸张中二次纤维的含量,在有的州(如加利福尼亚州),不但要求二次纤维的含量很高,而且还扩大到新闻纸以外的其他纸种中。最近在伦敦举行的“新闻纸的生产、应用及其未来”研讨会上,对于目前世界上许     

造纸用水合硅酸填料的制造方法

本发明是关于作为纸张填料用的水合硅酸(料浆)的制造方法。近年来,纸张有轻量化的倾向。在纸张轻量中要防止纸张的不透明度降低,一般在纸张中添加填料。在各种填料中,硅酸填料比其他种类的填料性能优越。本发明的制法是在有碱金属的存在下或     

预应力CFRP片材加固RC梁荷载-挠度分析

在已有混凝土梁外贴预应力破纤维增强聚合物(Carbon Fiber-Reinforced Polymer,简称CFRP)片材加固试验研究基础之上,基于平截面、界面无滑移等假定,考虑了CFRP片材端部有、无机械锚固及有、无初始荷栽持续作用等情况,建立了预应力纤维片材加固混凝土梁的全过程分析方法,编制了相应程序,比对了实验梁的荷栽-挠度实测曲线与计算曲线,吻合较好.其中,弯曲破坏的试验梁屈服荷载计算值与试验值误差平均值为3.88%,计算值与试验值比值的平均值为1.039,变异系数为0.027;极限承栽力计算值与试验值误差平均值为5.3%,计算值与试验值比值的平均值为1.054,变异系数为0.04,从而也说明了分析过程的正确性.     

协同填充改性聚四氟乙烯复合材料的研究进展

介绍不同无机纤维、不同无机粒子、无机纤维与无机粒子混合物、有机填料与无机填料混合物对聚四氟乙烯(PTFE)的协同改性研究进展,并对不同填料产生的协同效应进行了探讨.指出无机纤维与无机粒子混合物、有机填料与无机填料混合物协同改性PTFE的方法最具应用价值.     

美造纸用改性淀粉用墨继续增长

美国造纸专用淀粉的用量呈增长趋势。原因之一是抄纸工艺转变为碱性方法后,要采用添加淀粉(尤其是改性淀粉)的方法,才能保持纸张应有的强度和使用更多的无机填料。原因之二是造纸用纤维原料的变化。使用纤维长度     

改性玄武岩纤维水处理填料的理化性能分析

为了探究改性玄武岩纤维水处理填料的理化性能,研究了改性玄武岩纤维填料的结构及其吸水性能、充氧性能、表面自由能、亲水性能等,并与弹性填料、组合填料的性能进行对比。结果表明:改性玄武岩纤维填料中含有亲水基团,且表面比较粗糙;改性玄武岩纤维填料具有较高的含水率和回潮率,分别为64. 8%,11. 32%,其干燥速率低于弹性填料和组合填料;改性玄武岩纤维填料在20℃下的氧总传质系数为0. 383 7min~(-1),高于组合填料的0. 357 2 min~(-1),低于弹性填料的0. 421 4 min~(-1);改性玄武岩纤维填料与水的接触角为60. 52°,均低于其他两种填料,其表面自由能也最高。     

AKD-淀粉-碳酸钙复合填料的制备及应用

利用玉米淀粉、烷基烯酮二聚体(AKD)和重质碳酸钙(GCC)制备造纸用复合填料,并比较了复合填料与GCC填料的基本性能(如微观形貌、溶解性、溶胀度和接触角等)以及对纸张力学性能的影响。结果表明:随着AKD用量的增加,复合填料的溶胀度和溶解性略有下降,接触角明显增大;与GCC填料相比,复合填料能明显提高纸张的拉伸强度(99.1%)和耐破强度(98.9%),但纸张的光学性能略有降低;纸张的耐水性随着AKD用量的增加而明显提高;当w(AKD)=15%时,复合填料的应用效果最佳。     

Long‐term water uptake behavior of lignocellulosic‐high density polyethylene composites

Composites of different lignocellulosic materials and high‐density polyethylene were prepared and their long‐term water absorption behaviors were studied. Wood flour, rice hulls, newsprint fibers, and kenaf fibers were mixed with the polymer at 25 and 50 wt % fiber contents and 1 and 2% compatibilizer, respectively. Water absorption tests were carried out on injection‐molded specimens at room temperature for five weeks. Results indicated a significant difference among different natural fibers with kenaf fibers and newsprint fibers exhibiting the highest and wood flour and rice hulls the lowest water absorption values, respectively. Very little difference was observed between kenaf fiber and newsprint composites and between rice hulls and wood flour composites regarding their water uptake behavior. The difference between 25 and 50% fiber contents for all composite formulations increased at longer immersion times, especially for the composites with higher water absorption. Kenaf fiber composites containing 50% kenaf fibers exhibited the highest water diffusion coefficient. A strong correlation was found between the water absorption and holocellulose content of the composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3907–3911, 2006     

Determination of fiber orientation of cellulosic samples by x-ray diffraction

A method has been developed which permits the quantitative determination of fiber orientation in a cellulosic sample (paper, nonwoven or composite). From the measured fibril angle distribution function and the observed variation in intensity of the (002) plane of the x-ray pattern, a parameter governing the fiber distribution function is obtained analytically. The method is demonstrated for two different paper samples showing a narrow and a large fiber orientation distribution. The method is rapid for a series of samples involving the same fibers and does not involve any operator interpretation. It gives directly the average fiber orientation function from the bulk of the sample, not just from its surface as microscopic methods do. It can be particularly useful in the analysis of paper–polymer laminates.     

40．7％毒死蜱乳油中有效成分毒死蜱的气相色谱分析

40．7％毒死蜱乳油是在生产过程中使用毒死蜱原药和有关化学助剂配制而成,该制剂在白蚁等卫生害虫防治工作中占有很大的市场份额,为了确保卫生害虫防治工程质量,有必要对生产的40．7％毒死蜱乳油产品中有效成分毒死蜱含量进行分析并加以控制。据文献资料报道,毒死蜱的分析大多采用液相色谱分析方法,结合我国实际,采用内标法进行常规气相色谱分析方法尚未见文献报道。本文报导了气相色谱法选用SE－30为固定液及白色101担体作为固定相,正十八烷为内标物测定了40．7％毒死蜱乳油中的有效成分毒死蜱含量。本方法简便快速,灵敏度高,准确度和精密度较为满意。     

甲基毒死蜱的气相色谱分析

本文叙述了有机磷杀虫剂基毒死蜱定量分析方法。     

高效液相色谱法定量分析除虫脲

采用反相高效液相色谱法,以C18柱为固定相、甲醇+水为流动相,用DAD检测器在254nm波长下定量测定除虫脲的含量。本方法的变异系数为0.235%,平均回收率为99.92%,线性相关系数为0.9999。     

Composites from Newsprint Fiber and Polystyrene

This paper deals with the effect of processing conditions on the mechanical properties of composite material made from newsprint and polystyrene. A masterbatch compound with weight ratio of 50:50 (polystyrene/fiber) was prepared using a Brabender intensive type mixer. Composites with various percentage of fiber, e.g., 40, 30, 20, and 10% of fiber were obtained by adding the measured amount of polymer to the masterbatch followed by another mixing period of time. Test samples were compression molded into shoulder-shaped test specimens, using a steam-heated press, and, kept in room conditioning at 23°C and 50% of relative humidity for a week 48 h prior to testing. The Young's modulus and the strength at break were evaluated, and the averages of six measurements were reported.

Test results showed that newsprint loading level has a significant impact on mechanical performance of the resulting composites. Tensile strength increased at first linearly with newsprint content, then reached asymptote at higher level of newsprint content 40% or more. As the Young's modulus is concerned, there is a linear relationship between tensile Young's modulus and fiber concentration as proposed by the various models in the literature.     

禾草特原油的气相色谱分析

本文叙述了采用ＯＶ－２２５玻璃填充柱，以邻苯二甲酸二乙酯做内标，用气相色谱定量分析禾草特原油的方法。本方法变异系数０．１３％，回收率９９．８％。     

纤维水泥基材料抗冻性与孔结构关系的变化规律

本文探究了冻融循环过程中纤维水泥基材料性能的变化规律与劣化机理。采用压汞法测量纤维水泥基材料在未经历冻融和经历300次冻融循环后,其孔隙特征参数(总孔体积、总孔隙率、最可几孔径、临界孔径和平均孔径)与体积百分比(无害孔、少害孔、有害孔和多害孔)。并运用灰色相对关联度将纤维水泥基材料在未经历冻融和经历300次冻融循环后的抗冻性指标与孔隙特征参数和体积百分比分别进行关联分析。研究表明,随着冻融循环次数的增加,纤维水泥基材料的质量损失率逐渐降低,即质量呈现增加趋势,抗压强度、动弹性模量和超声波波速均有不同程度的减小。其内部孔隙特征参数和体积百分比的变化规律可以解释抗冻性指标产生变化的微观原因。经历过冻融循环后,纤维水泥基材料的平均孔径和孔隙体积百分比与抗冻性指标的相对关联度有明显的提高。     

Newsprint paper waste as a fiber reinforcement in rubber composites

The investigation of the economical use of lignocellulose waste, which is one of the environmental problems facing third‐world nations, is ongoing. In this study, we intended to increase the use of newsprint fibers in the rubber industry. For this reason, we treated newsprint fibers with sodium silicate and magnesium chloride, and we examined the water retention values and thermal degradation analyses of the treated fiber waste. The activation energy of degradation was evaluated with the Coats–Redfern method of analysis. The effects of the addition of different amounts [0–60 parts per hundred parts of rubber by weight (phr)] of untreated and treated newsprint fibers on both the electrical and mechanical properties of two different types of rubber (natural rubber and acrylonitrile rubber) were studied. This study led us to the conclusion that the addition of treated newsprint fiber waste at a concentration of 40 phr could lead to an end product characterized by good electrical and mechanical properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 469–478, 2004     

Newsprint paper waste as a fiber reinforcement in rubber composites

The investigation of the economical use of lignocellulose waste, which is one of the environmental problems facing third‐world nations, is ongoing. In this study, we intended to increase the use of newsprint fibers in the rubber industry. For this reason, we treated newsprint fibers with sodium silicate and magnesium chloride, and we examined the water retention values and thermal degradation analyses of the treated fiber waste. The activation energy of degradation was evaluated with the Coats–Redfern method of analysis. The effects of the addition of different amounts [0–60 parts per hundred parts of rubber by weight (phr)] of untreated and treated newsprint fibers on both the electrical and mechanical properties of two different types of rubber (natural rubber and acrylonitrile rubber) were studied. This study led us to the conclusion that the addition of treated newsprint fiber waste at a concentration of 40 phr could lead to an end product characterized by good electrical and mechanical properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3410–3420, 2004