SFP木质素在钻井液中的作用效能

木质素磺酸盐及其改性产品是一大类传统的钻井液稀释剂，SFP木质素是用亚硫酸盐－甲醛－蒽醌法对麦草制浆的废液生产的一种木质素磺酸盐。实验表明，SFP木质素在钻井液中有稀释、起泡及絮凝三种作用。因此，SFP木质素及其改性产品可作为钻井液稀释剂和起泡剂，也可作为处理废钻井液的絮凝剂。     

酸性亚硫酸盐法荻苇浆制浆废液中低分子有机物的GC-MS分析

亚硫酸氢镁法荻苇浆制浆废液经超滤提取木质素磺酸盐后，超滤滤过液经三氯甲烷萃取，并将可萃取有机物分为酸性和中性二个组份，采用GC－MS技术对二个组份进行了定性分析。酸性组份中检测到的主要成分为脂肪酸和低分子木质素降解产物。     

改性木质素磺酸盐GCL2-D1的缓蚀机理

采用凝胶渗透色谱、化学滴定法、紫外差示光谱法、环境扫描电镜、交流阻抗谱、俄歇能谱等方法研究了改性前后木质素磺酸盐的结构特征和缓蚀性能,揭示了缓蚀作用机理。改性后木质素磺酸盐的分子量从11048提高到29381,磺酸基含量从9.04%提高到11.2%,羧基含量从5.81%提高到15.84%,在溶液中的构型由球状变为直链状,在金属表面吸附膜层S、Ca、C含量均增加,表明改性木质素磺酸盐在金属表面吸附点增多,吸附量增大。电化学测试结果表明改性木质素磺酸盐（简称GCL2-D1）属于混合抑制型缓蚀剂,腐蚀介质中掺加100 mg•L^-1GCL2-D1能使腐蚀过程电荷传递电阻从564 Ω增加至20680 Ω,金属/溶液界面电容从2.84 mF降低至0.041 mF,说明改性后的木质素磺酸盐能够在金属表面形成致密的膜层,从而抑制金属腐蚀。     

木质素磺酸盐减水剂改性研究进展

筒述了木质素磺酸盐减水剂的改性方法和性能研究的最新进展.物理改性方法包括木质素磺酸盐的分离提纯和对其分子量进行分级;化学改性方法主要有氧化、磺化、酚化、羟甲基化、曼尼希反应和接枝共聚等;木质素磺酸盐减水剂对水泥凝结时间、强度、水化过程的影响以及在水泥颗粒表面吸附行为是其性能研究的主要方面.最后总结认为,进一步加强改性方...     

含木质素基混凝土外加剂的研究进展

综述了木质素在混凝土外加剂中的应用。工业木质素,尤其是木质素磺酸盐,可以充当混凝土减水剂、缓凝剂、引气剂和泵送剂。由于未经改性的工业木质素性能不够理想,为了提高木质素基混凝土添加剂的性能,宜对其进行适当的改性。碱木质素经过氧化、磺化、磺甲基化、接枝共聚等改性后,可以得到具有良好性能的混凝土外加剂。     

木素磺酸盐接枝共聚的研究——Ⅰ.接枝方法和接枝共聚物的物化特性

本文研究了由H_2O_2—Fe(Ⅱ)引发木素磺酸盐和丙烯酸单体的接枝共聚反应,比较了不同的接枝方法(一步法和连续法)对接枝共聚物粘度和分散性能的影响以及分子量分布的变化。研究结果表明,接枝共聚反应能大大提高木素磺酸盐的分散能力。连续法接枝共聚物的物化性能优于一步法,具有高分散性和低溶液粘度的特点。接枝共聚物的羧基含量随丙烯酸单体的用量增加而增加,而酚羟基含量较接枝前有所降低。     

改性木质素磺酸盐对水中Cr6+的吸附

对改性木质素磺酸盐处理含Cr6+废水进行了研究,考察了改性木质素磺酸盐投加量、吸附时间、pH值和温度对吸附效果的影响. 实验结果表明,在优化实验条件下,改性木质素磺酸盐投加量为3 g、吸附时间为1 h及pH值4~7、常温条件下,可以使水中Cr6+含量低于0.5 mg/L,改性木质素磺酸盐对Cr6+的吸附符合Freundlich等温方程. 改性木质素磺酸盐是一种高效的重金属离子吸附剂.     

溶剂型木质素改性三元乙丙橡胶的研究

探索了溶剂型高沸醇(HBS)木质素接枝马来酸酐-纳米SiO2和溶剂型酶解(EH)木质素-纳米SiO2复合物对乙丙橡胶的改性效果。结果表明,溶剂型木质素可以和纳米SiO2形成复合材料,添加HBS木质素-纳米SiO2和EH木质素-纳米SiO2复合物均能显著改善三元乙丙橡胶的扯断伸长率,由改性前的277.1%分别提高到399.71%和354.43%,但拉伸强度略有降低;改性后的硫化三元乙丙橡胶具有优良的耐老化性能,显示它们与普通改性添加剂的不同,有望得到实际应用。     

接枝磺化木质素高效减水剂的配伍性能研究

以酸析木质素为原料,通过接枝、磺化和缩合制得接枝磺化酸析木质素GSAL,研究了它与木质素磺酸盐和消泡剂的配伍性能。结果表明:GSAL分别与木质素磺酸盐及其改性产品复配,可得到减水剂GSAL1和GSAL2。当水灰比为0.29、掺量w(GSAL1)=0.6%时,水泥净浆流动度达243mm;掺量w(GSAL2)=0.8%时,水泥净浆初凝时间延长110min,终凝时间延长约7h。掺量w(GSAL1)=0.8%时,水泥净浆减水率为21.4%,砂浆3d和7d的抗压强度比分别为163%和143%,其对水泥的减水增强作用超过了萘系高效减水剂FDN。GSAL与消泡剂的复配产品起泡性降低,水泥净浆流动度、新拌砂浆密度和砂浆抗压强度比均增大,GSAL与磷酸三丁酯配伍后的综合性能最佳。     

利用原子转移自由基聚合法制备SiO_2/PAM纳米复合材料

为了改善二氧化硅(SiO_2)纳米粒子在聚合物基体中的分散性,采用原子转移自由基聚合(ATRP)法将聚合物接枝到纳米SiO_2表面。用甲苯-2,4-二异氰酸酯(TDI)对纳米SiO_2表面进行改性,然后与2-羟基-2′-乙基-2′-溴丙酸乙酯(HMB)反应,在表面引入ATRP引发剂,合成纳米二氧化硅颗粒(SiO_2-Br)。红外光谱(FT-IR)分析、热失重分析(TGA)和X-射线光电子能谱(XPS)结果表明,成功制备了SiO_2-Br引发剂,并通过ATRP法将聚丙烯酰胺(PAM)接枝到纳米SiO_2表面。通过凝胶渗透色谱(GPC)和分散性实验对改性后的样品进行了表征,结果表明,改性后的纳米SiO_2在甲苯中具有良好的分散性。     

木素磺酸盐接枝共聚的研究——Ⅱ.接枝反应机理

本文研究了木素磺酸盐和丙烯酸单体的接枝共聚机理。通过比较木素磺酸盐和模型物接枝前后酚羟基的含量和碱性硝基苯氧化产物得率的变化,对接枝反应位置进行了研究。研究结果表明,接枝反应发生在萃环C_5位上,也可以在酚羟基上进行。分子轨道法对木素磺酸模型物的计算结果进一步证实了以上结论。     

复合聚电解质凝胶的制备与性能研究 Ⅰ.表面性能对凝胶的影响

采用柱状灯芯技术(Column Wicking Technique)研究了三种不同阳离子的木质素磺酸盐(木质素磺酸钠、钙和镁)的表面性能,同时应用电导率测试法对聚丙烯酰胺(PAAM)/木质素磺酸盐聚电解质凝胶的形成过程进行了研究。结果表明:木质素磺酸钙具有最高的表面能,而木质素磺酸钠的表面能最低。结合对凝胶过程的研究进一步发现,相对于聚丙烯酰胺凝胶来说,加入木质素磺酸盐对聚电解质凝胶的体系的影响是非常明显的,即木质素磺酸盐表面能大,则所形成的凝胶的电导率就小。上述结论也在实验过程得到了验证,根据手感可发现,在三种木质素磺酸盐中,加入木质素磺酸钙所形成的聚电解质凝胶具有较好的致密性和较高的强度。     

木质素磺酸镁对不同纤维素原料酶解的影响机制

为探讨木质素磺酸镁作为辅助添加剂在纤维原料酶解过程的作用机制,以两种木质素磺酸镁为研究对象,考察了不同来源木质素磺酸镁组构差异及其在不同纤维原料酶解过程中的作用。研究发现,商品木质素磺酸镁较自制木质素磺酸镁具有更高的磺化度,但自制木质素磺酸镁具有更高总羟基相对含量。商品木质素磺酸镁和自制木质素磺酸镁对微晶纤维素酶解均有促进作用;对于木质纤维原料酶解,两种木质素磺酸镁对水热法预处理物料均有抑制作用。对亚硫酸氢镁预处理物料酶解,仅低浓度的自制木质素磺酸镁表现出促进作用。该研究为解释木质素磺酸镁对纤维素原料酶解的影响机制提供了理论依据。     

Graft copolymerization of lignosulfonate and styrene

A study was made of the graft copolymerization of calcium lignosulfonate with styrene. Heterogenous copolymerization were carried out with methanol as swelling medium, using ferrous ion as catalyst, and ozone and/or hydrogen peroxide as initiator. When using peroxide alone as initiator, monomer conversion was low; after ozonization of lignosulfonates, monomer conversion increased considerably and the grafting efficiency, as well as degree of lignosulfonate grafted, was improved. At 55°C, a 10-fold increase in conversion was observed for reactions with ozone-pretreated lignosulfonates. The investigated factors that affected the graft copolymerization were: the amount of peroxide and ozone charged, the reaction temperature and the ratio of styrene/methanol.     

温度、pH双重敏感聚氨酯膜的制备及其智能特性

以温敏聚氨酯(TSPU)材料为基膜,利用表面接枝改性技术将带有对pH敏感的官能团(丙烯酸)引发接枝到基膜的表面,成功制备了一种对温度、pH双重敏感的聚氨酯膜.红外光谱分析发现,在接枝膜的谱图上出现了羧基的特征吸收峰,说明丙烯酸已成功接枝到TSPU膜上.扫描电镜对接枝膜形貌观察表明,在TSPU膜的表面,具有明显的聚丙烯酸...     

Keramische Membrantechnologie für die Verfügbarmachung biogener Stoffströme

Within the scope of this research work, an efficient membrane-based process with ceramic ultrafiltration membranes was developed for the recovery of purified lignosulfonates from the spent sulfite liquor of chemical wood pulping. The aim was to separate the lignosulfonates from low-molecular organic impurities (sugar, carboxylic acids, etc.) and process chemicals, to concentrate them, and to make them available for a targeted further use. One further aspect of the project was the separation of the products (target molecules) of lignosulfonate degradation using ceramic membrane technology.     

木素磺酸盐和丙烯酸电化学接枝共聚反应的研究

木素磷酸盐与丙烯酸溶液在以二氧化铅为阳极、不锈钢为阴极的无隔膜电解槽中电解,可以发生电化学接校共聚反应。接技产物的红外话留在1724cm－1处出现强的谈基吸收峰;接技产物中羧基的含量明显增大;接技产物的表面活性明显改善,1％的接技产物水溶液与大庆原油的界面张力达到10-1mN／m,表面张力也明显降低;接技产物具有很好的分散性能。     

Applicability of Oxidative Systems to Initiate Grafting on and Bonding of Wood

Graft polymerization techniques were applied to induce bonding in wood composites. Wood surfaces were activated with an oxidant such as hydrogen peroxide, nitric acid, peracetic acid, potassium ferricyanide or sodium dichromate. The activated wood surfaces were then chemically crosslinked with polymerizing materials such as furfuryl alcohol, ammonium lignosulfonate, mixtures of lignosulfonate with furfuryl alcohol, with formaldehyde or with maleic acid. The wood composites were pressed using conventional manufacturing conditions. The strength and water resistance properties of the wood composites were suitable for exterior structural applications. The various methods proposed to induce chemical bonding of wood are briefly reviewed.     

Fouling control in a submerged membrane‐bioreactor by the membrane surface modification

To improve the antifouling characteristics, polypropylene microporous membranes (PPHFMMs) were surface‐modified by the sequential photoinduced graft polymerization of acrylic acid and acrylamide. The grafting density and the grafting chain length, which played important roles in the antifouling characteristics, were controlled in the first and the second step, respectively. The ATR/FTIR results clearly indicated the successful modification on the membrane surface. The static water contact angle of the modified membrane reduced obviously with the increase of the grafting chain length. The contact angle of the acrylic acid modified membranes was lower than that of the acrylamide modified membrane with similar grafting chain length. The grafting chain length increased with the increase of UV irradiation time and monomer concentration. The grafting chain length of poly(acrylic acid) (PAAc) was lower than that of the polyacrylamide (PAAm) under the same polymerization conditions. Pure water flux for the modified membranes increased with the increase of grafting chain length, and had maximums. The antifouling characteristics of the modified membranes in a submerged membrane‐bioreactor (SMBR) were evaluated. The modified membranes showed better filtration performances in the SMBR than the unmodified membrane, and the acrylic acid grafted membrane presented better antifouling characteristics than acrylamide modified membranes. The results demonstrated that the surface carboxyl‐containing membranes were better than the surface amido‐containing membranes. The results of Pearson correlations demonstrated that the PAAc modified membranes with longer grafting chain length had higher flux recoveries, while the PAAm modified membranes with longer grafting chain length had lower flux recoveries. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010