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AKD生产中三乙胺的回收和利用 总被引:2,自引:0,他引:2
从副产物三乙胺盐酸盐中回收三安对降低AKD生产成本至关重要。采用了物理和化学相结合的方法使回收三乙胺的含水量低于0.1%,满足了AKD生产的要求。 相似文献
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介绍了国内外烷基烯酮二聚体(AKD)中性施胶剂的发展情况,并对AKD的合成原理(脂肪酸的酰氯化和脂肪酸的脱氯化)、施胶机理、影响AKD施胶效率的因素(乳液存放时间和条件、纸张类型、pH值和总碱度、Zeta电位、填料以及其他添加剂等)和AKD的改性等进行了综述。 相似文献
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AKD造纸施胶剂制备的研究 总被引:5,自引:0,他引:5
本文用烷基烯酮二聚体(AKD)单体为分散质、水为分散相,加入助剂,在高压均浆器内进行乳化,制得贮存期为二个月的AKD乳液。研究了乳化剂的品种、阳离子淀粉、增稠剂、乳化体系的酸值、温度及时间对制备AKD乳液的影响。 相似文献
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AKD专用高分子表面活性剂的性能研究 总被引:2,自引:0,他引:2
设计并合成了一种高分子表面活性剂,用FTIR、DSC、GPC分析手段研究了高分子表面活性剂的分子结构,并对其表面张力进行了测定。测试结果显示,4种单体都参与了共聚反应,无均聚物存在,高分子表面活性剂的重均分子量为58 536,数均分子量为16 812,多分散性系数为3.48,说明相对分子质量(简称分子量)的分散程度较小。温度为25℃时,高分子表面活性剂的CMC为0.8 mmol/L,γCMC为50.1 mN/m。当m(高分子表面活性剂)/m(烯酮二聚体)=0.23时,可制备出稳定的烯酮二聚体(AKD)乳液,且该AKD乳液质量占绝干浆质量的0.13%时,浆内施胶度可达200 s以上。用马尔文纳米粒度及Zeta电位分析仪测定出AKD乳液的平均粒径为574.4 nm,Zeta电位为11.16 mV。通过TEM观察,AKD乳胶粒子在高分子表面活性剂的包裹下呈核壳结构,并且形成水包油乳液。该高分子表面活性剂具有良好的表面活性与应用潜力。 相似文献
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Seyedehsan Hosseini Robin Nilsson Anna Ström Anette Larsson Gunnar Westman 《Polymer Composites》2024,45(1):825-835
Alkyl ketene dimers (AKDs) are known to efficiently react with cellulose with a dual polarity in their structure: a polar component and a nonpolar component. AKD of three different carbon chain lengths, 4, 10, and 16 carbons have been synthesized, and thermomechanical pulp (TMP) fibers were modified by them. The modification of TMP fibers with AKD resulted in an increased water contact angle, showing the presence of the AKDs on the TMP fibers and a new carbonyl peak in the IR spectra, suggesting modification of the TMP fibers with AKD groups. Calculating the Hansen solubility parameters of AKD and AKD conjugated to TMP in polypropylene (PP) indicates improved compatibility, especially of longer chain AKD and TMP AKD. The rheological studies of the composites showed that the AKD with the longest carbon chain decreases the melt viscosity of the PP-TMP-AKD composite, which combined with the shape and the color of the extruded composite filaments indicates improved flow properties and reduced stress build up during processing. The research findings demonstrate the ability of AKD to enhance the dispersibility and compatibility of natural fibers with PP. 相似文献
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针对某造纸厂再生纸抄造工程实际中,烷基烯酮二聚体(AKD)表面施胶挂面再生纸耐水性能提高不明显的质量问题,采用接触角、红外光谱(FTIR)、热重(TG)、X射线光电子能谱技术(XPS)、扫描电镜(SEM)、能谱(EDS)等研究方法,对纸厂生产的AKD施胶挂面再生纸纸样进行表征研究。结果表明,纸样接触角变化表现两面性差异,施胶纸样正面初期接触角为114.5°,反面初期接触角为118.5°,正面临界润湿接触角(≥90°)时间不足9min,反面临界润湿接触角为9min,纸样不具备长效耐水性,AKD施胶体系对纸张长效耐水性的贡献不明显;施胶后AKD特征官能团β-乙烯基丙内酯消失,施胶纸样和施胶萃取纸样在不同氛围下的失重行为不同,原子组成和原子价态化学环境不同,施胶纸样中含有可被四氢呋喃(THF)抽出的可溶物(AKD水解产物酮),水解产物酮相对含量高于99.0%。AKD不良施胶的主要原因在于施胶体系配伍不当,导致AKD与纤维素酯化接枝反应的具有长效耐水产物的量不足。 相似文献
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Invertase was immobilized onto the dimer acid‐co‐alkyl polyamine after activation with 1,2‐diamine ethane and 1,3‐diamine propane. The effects of pH, temperature, substrate concentration, and storage stability on free and immobilized invertase were investigated. Kinetic parameters were calculated as 18.2 mM for Km and 6.43 × 10?5 mol dm?3 min?1 for Vmax of free enzyme and in the range of 23.8–35.3 mM for Km and 7.97–11.71 × 10?5 mol dm?3 min?1 for Vmax of immobilized enzyme. After storage at 4°C for 1 month, the enzyme activities were 21.0 and 60.0–70.0% of the initial activity for free and immobilized enzyme, respectively. The optimum pH values for free and immobilized enzymes were determined as 4.5. The optimum temperatures for free and immobilized enzymes were 45 and 50°C, respectively. After using immobilized enzyme in 3 days for 43 times, it showed 76–80% of its original activity. As a result of immobilization, thermal and storage stabilities were increased. The aim of this study was to increase the storage stability and reuse number of the immobilized enzyme and also to compare this immobilization method with others with respect to storage stability and reuse number. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1526–1530, 2004 相似文献
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以三乙胺和硬脂酰氯为原料,采用无溶剂法制备了烷基烯酮二聚体(AKD),为了避免蒸馏法回收过量三乙胺所带来的高能耗,提出了一种新的工艺对AKD后处理过程进行改进,反应产物在热过滤除去三乙胺盐酸盐后,在低温下过滤得到AKD,所得滤液循环使用。研究了不同参数对反应收率和AKD纯度的影响,最佳反应温度为60℃,反应时间为1.5 h。当三乙胺和硬脂酰氯的摩尔比R_(TEA/STC)5时,尽管首次采用新鲜原料时反应收率较低,但并不影响后续的循环反应收率,循环反应收率可达86%,而且较高的原料配比可使反应在较低的黏度下进行。多次的循环实验表明,采用文中所提出的方法,操作易于控制、能耗低、反应条件温和,值得进行工业推广。 相似文献
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