AKD合成中三乙胺的回收

本文叙述了三乙胺盐酸盐经碱中和、蒸馏、生石灰脱水、再蒸馏等步骤回收三乙胺的方法．回收的三乙胺可重新应用于ＡＫＤ的合成．     

EAK分子间炸药的热分解

通过 Ｄ Ｓ Ｃ分析研究了 Ｅ Ａ Ｋ（乙二胺二硝酸盐硝酸铵硝酸钾）低共熔物分子间炸药的热分解特性,测定了 Ｅ Ａ Ｋ 的分解动力学参数。研究表明氧化剂 Ａ Ｋ 和还原剂 Ｅ Ｄ Ｄ 相互作用的结果导致 Ｅ Ａ Ｋ 表现为快速的自催化分解。     

2,2-二烷基-2-烷胺基苯乙酮/二芳基酮复合引发体系光聚合的加和作用

本文研究了２，２－二烷基－２－烷胺基苯乙酮（α－ＡＫ）和二芳基酮（ＤＡＫ）（包括二苯酮（ＢＰ）、米酮（ＭＫ）、二乙基蒽醌（ＥＡＱ）和硫杂蒽酮（ＴＸ））复合体系的加和作用．体系中ＤＡＫ的添加显著地改善了α－ＡＫ在近紫外光区长波段无吸收的缺陷．光聚合实验比较了ＤＡＫ的效果，其中氯代ＴＸ、ＢＰ增效作用显著，使聚合反应速度增加１．３～１．５倍，而ＭＫ和ＥＡＱ没有明显影响．同时还研究了溶剂极性、浓度和取代基的影响．结果表明，溶剂极性增加起负影响，α－ＡＫ／ＤＡＫ等摩尔浓度效果最佳和氯代ＴＸ活性高于烷基取代ＴＸ．通过吸收光谱α－ＡＫ／ＤＡＫ复合体系的加和作用机制进行了研究，结果证明三重态的能量传递敏化反应和光还原反应两种反应过程并存，它们的贡献因二芳酮不同而有差异．     

填补硬度空白的苯乙烯嵌段共聚物

ＫＲＡＴＯＮ聚合物公司称,采用ＫｒａｔｏｎＤ-ＫＸ-２２４苯乙烯嵌段共聚物,通过配混能更容易产生用于制鞋业的具有良好平衡性能的配方。它填补了其它各种组分硬度范围的空白,配混可以生产易于在传统和现代注塑设备上加工的高性能化合物。该公司帮助意大利一家鞋底厂开发高性能的新型聚合物。大多数以ＳＢＳ为基础的传统鞋底化合物需要含有硬、软聚合物的混合物,而ＫｒａｔｏｎＤ-ＫＸ-２２４可以单独使用也可以与其它高级组分混合使用。添加ＫｒａｔｏｎＤ-ＫＸ-２２４后,弹性更好,且具有减震作用。加工废料可以回收,从而降低生产成本。…     

AKD造纸施胶剂制备的研究

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。     

2,2—二烷基—2—烷胺基苯乙酮／二芳基酮复合引发体系光聚合…

本文研究了２，２－二烷基－２－烷胺基苯乙酮和二芳基酮，米酮，二乙基蒽醌和硫杂蒽酮复合体系的加和作用。体系中ＤＡＫ的添加显著地改善了α－ＡＫ在近紫外光区长波段无吸收的缺陷。光聚合实验比较了ＤＡＫ的效果，其中氯代ＴＸ，ＢＰ增效作用显著，使聚合反应速率增加１．３－１．５倍，而ＭＫ和ＥＡＱ没有明显影响。同时还研究了溶剂极性，浓度和取代基的影响。结果表明，溶剂极性增加起负影响，α－ＡＫ／ＤＡＫ等摩尔浓度效果     

立体交叉管线施工中小角度弯头的下料 --正弦函数计算法

在石油化工厂的工艺管线施工中 ,经常会碰到如图 1所示的交叉管线的立体图。图 1　立体交叉管线的立体图图中线段ＤＥ和线段ＡＫ分别为上水平管和下水平管 ,ＤＥ和ＡＫ在空中相互垂直 ,即ＤＥ⊥ＡＫ ;Ｈ为ＤＥ和ＡＫ之间的垂直距离 ,条件是 0≤Ｈ≤ 2Ｒ ;Ｒ为弯头中心线的弯曲半径 ;ＡＢ为中心线弯曲半径为Ｒ、角度为 90°的下弯头 (如图 2所示 )。图 2　 90°弯头ＢＤ为中心线弯曲半径为Ｒ、角度为α的上弯头 (如图 3所示 ) ,条件是 0°≤α≤ 90°。图 3　α角度的弯头如何求出α的下料角度是下料的关键 ;Ａ、Ｂ、Ｄ点分别为线段ＡＫ与Ａ…     

LARGE SCALE PURIFICATION OF PHOSPHOGLYCERATE KINASE（PGK） AND GLYCERALDEHYDE 3－PHOSPHATE DEHYDROGENASE（GAPDH） FROMYELLOW PEAS BY PEG／REPPAL PES AQUEOUS TWO PHASE SYSTEM AND ION EXCHANGE CHROMATOGRAPHY

ＬＡＲＧＥＳＣＡＬＥＰＵＲＩＦＩＣＡＴＩＯＮＯＦＰＨＯＳＰＨＯＧＬＹＣＥＲＡＴＥＫＩＮＡＳＥ（ＰＧＫ）ＡＮＤＧＬＹＣＥＲＡＬＤＥＨＹＤＥ３－ＰＨＯＳＰＨＡＴＥＤＥＨＹＤＲＯＧＥＮＡＳＥ（ＧＡＰＤＨ）ＦＲＯＭＹＥＬＬＯＷＰＥＡＳＢＹＰＥＧ／ＲＥＰＰＡＬ...     

凯洛格合成氨生产新技术

凯洛格公司在合成氨生产技术方面一直处于世界领先的地位，最近该公司又开发出了４种先进的合成氨生产技术：ＫＡＡＰ、ＫＲＥＳ、ＫＤＡＣ、ＫＩＣＳ，本文简述这４种新技术发展概况。     

EXPERIMENTAL INVESTIGATION OF KINETIC AND TRANSPORT PARAMETERS IN A WALL－COOLED FIXED－BED REACTOR

ＥＸＰＥＲＩＭＥＮＴＡＬＩＮＶＥＳＴＩＧＡＴＩＯＮＯＦＫＩＮＥＴＩＣＡＮＤＴＲＡＮＳＰＯＲＴＰＡＲＡＭＥＴＥＲＳＩＮＡＷＡＬＬ－ＣＯＯＬＥＤＦＩＸＥＤ－ＢＥＤＲＥＡＣＴＯＲＺｈｅｎ－ＭｉｎＣＨＥＮＧａｎｄＷｅｉ－ＫａｎｇＹＵＡＮ（ＵＮＩＬＡＢＲｅｓｅ...     

AKD生产中三乙胺回收工艺改进设计

通过对AKD生产中三乙胺回收工艺的分析、比较,提出采用氢氧化钠脱酸、吸水代替氢氧化钙脱酸、氧化钙吸水,并利用MVR蒸发结晶技术,得到副产品氯化钠固体。改进后,提高了三乙胺的回收利用率,减少了环境污染,增加了经济效益。     

Unique alkyl ketene dimer Pickering‐based dispersions: Preparation and application to paper sizing

Herein, particle‐stabilized alkyl ketene dimer (AKD) dispersions were prepared using dodecyl trimethyl ammonium chloride (DTAC)‐modified laponite as the stabilizer, and sodium alginate (SA) as the protective colloid. The modification of laponite particles with DTAC, which was characterized by transmission electron microscopy, infrared spectroscopy, and X‐ray diffraction technique, moderately decreases the negative zeta potential and causes the dehydration of laponite particles. Consequently, the modification of laponite promotes the absorption of laponite particles on AKD droplets/spherical particle surfaces, leading to formation of AKD dispersions with reduced particle size and enhanced uniformity when DTAC‐to‐laponite mass ratio is <1%. Meanwhile, SA significantly increases the stability of the AKD dispersions and provides stable AKD dispersions with smaller particles when SA‐to‐AKD mass ratio is <0.08%. By means of confocal laser scanning microscopy, scanning electron microscope imaging and energy dispersive spectroscopy (EDS)/EDS mapping, the function of DTAC‐modified laponite particles in stabilization of AKD dispersions was found to include both formation of a particle barrier around AKD particles and an increase in the moving resistance of AKD particles by laponite particles with SA. AKD dispersions at a DTAC‐to‐laponite mass ratio 1.0% and SA‐to‐AKD mass ratio 0.054% provide the smallest droplet size and best sizing performance. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45730.     

Asymmetric Polymer Bridging Between Starch‐Coated Colloidal Particles and Pulp Fibres by Cationic Polyacrylamide

Internal sizing agents are commonly used as additives in papermaking to impart hydrophobicity to paper. They are commonly added in the form of colloidal particles, stabilized by cationic starch. As an example we studied the deposition of micron‐sized Alkyl Ketene Dimer (AKD) particles on pulp fibres by cationic polyacrylamide (cPAM), a common flocculent. It was found that cPAM did not adsorb on AKD particles stabilized by cationic starch. Despite this inability to adsorb, cPAM was found to drastically improve the deposition of AKD particles on pulp fibres. This deposition was ascribed to asymmetric polymer bridging, a phenomenon observed by us before, while studying clay deposition on fibres by polyethylene oxide. In asymmetric polymer bridging between two types of particles, the bridging polymer first adsorbs on one type of particle, since it is unable to adsorb on the second type. Asymmetric polymer bridging occurs when the enthalpy gain on both surfaces exceeds the entropy loss. The kinetics of AKD deposition on fibres was found to agree with the predictions of the asymmetric bridging theory. In addition, an increase in bond strength with time was found, due to starch and cPAM reconfiguration. The increase in AKD retention by cPAM is also observed in experiments on a laboratory twin‐wire sheet former. Asymmetric polymer bridging by cPAM between starch‐coated AKD particles and fibres is compared with classical polymer bridging by cPAM between fibres and AKD particles coated by carboxymethylcellulose.     

Influence of Fillers on Sizing Efficiency and Hydrolysis of Alkyl Ketene Dimer

The influence of various fillers on sizing efficiency, adsorption and hydrolysis of alkyl ketene dimer (AKD) has been investigated. Results indicated that the precipitated calcium carbonate (PCC) improved AKD retention, both bound and unbound. The sizing efficiency was reduced as PCC contents increased, which might be attributed to the decrease in the relative AKD dosage to fibres and AKD hydrolysis promoted by PCC. Less amount of AKD was adsorbed on PCC, compared with calcined clay and TiO₂ fillers under the same conditions. Hydrolysis studies indicated that PCC had a more detrimental effect on AKD hydrolysis than clay and TiO₂.     

Alkyl ketene dimer modification of thermomechanical pulp promotes processability with polypropylene

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.     

烷基烯酮二聚体施胶体系对挂面再生纸表面不良施胶的成因剖析

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。     

AKD专用高分子表面活性剂的性能研究

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。     

AKD的化学合成

以硬脂酸、棕榈酸、氯化亚砜、三乙胺为原料,经过酰氯化、缩合和浓缩三步反应合成了中性施胶剂AKD。实验得到的最佳工艺条件为:氯化亚砜与脂肪酸的摩尔比为1.3∶1,酰氯化反应时间为3h,反应温度为60～65℃;缩合反应温度为45℃,反应时间为5h;浓缩初期水浴温度为50～55℃,后期水浴温度为90℃,真空度为-0.098MPa,反应时间为2h。所得AKD为微黄色蜡状固体,熔点为44～48℃,碘值(以100g样品计)均≥40.2g,含量≥80%。     

AKD改性羟乙基纤维素的合成及使用性能

采用异丙醇为溶剂,利用淤浆法在羟乙基纤维素(HEC)的制备过程引入一种改性试剂烷基或链烯基乙烯酮二聚体(AKD)以对其进行改性,比较改性HEC与未改性HEC的耐温性、耐盐性及耐酶性等使用性能,测试结果表明,AKD的引入使得改性HEC的使用性能得到一定的提高。     

烷基烯酮二聚体(AKD)中性施胶剂的研究进展

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。