浆内助剂改善纸模制品表观平滑度的研究

目的研究阳离子淀粉(CS)和阳离子聚丙烯酰胺(CPAM)与加入烷基烯酮二聚体(AKD)乳液浆料的滤水性能及对纸模制品表观平滑度的影响。方法向废旧单面瓦楞纸板浆料中分别加入CS与AKD,CPAM与AKD来制作平板纸模试样。结果相比于只添加AKD的浆料,先加入CS糊化液或CPAM后再加入AKD,浆料的滤水时间和打浆度都有不同程度的降低,且随着CS和CPAM用量的增加,试样的摩擦因数先减小后增加,即试样表面平滑度先提高后降低。结论 HSCS-02型季铵型阳离子玉米淀粉具有较好的助滤性能,能较好地改善纸模制品的表观平滑度,其最佳质量分数为3%;CPAM的助滤性能和对纸模制品表观平滑度的改善作用优于CS,其最佳质量分数为0.06%。     

基于相反转法纳胶囊相变材料的制备与表征

将低能乳化法应用到纳胶囊的制备过程中,以山梨糖醇酐油酸酯(Span80)与失水山梨醇单油酸酯聚氧乙烯醚(Tween80)为复合乳化剂,成功合成了以正十八烷为芯材,脲醛树脂为壁材的相变材料纳胶囊。采用扫描电子显微镜、Zeta电势、差示扫描量热分析和热重等表征手段对纳米乳液和纳胶囊的性能进行了表征分析,研究结果表明,随着乳化剂含量的增加,乳液的粒径变小且分布变窄,同时稳定性增加;制备的纳胶囊平均粒径在500 nm左右,表面相对光滑;随着壁材单体含量的减少,纳胶囊的热函值减小,被包覆的囊芯含量下降。     

以松香为功能单体的苯乙烯丙烯酸酯乳液(SAE)表面施胶剂的制备及表征

利用低黏度阳离子淀粉(CS-8)的乳化、分散作用,采用无皂乳液聚合的方法,以苯乙烯(St)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)为主要原料,引入松香作为功能单体,合成了核壳型阳离子苯乙烯丙烯酸酯乳液(SAE)。讨论了其合成影响因素,并优化了合成工艺条件;用扫描电子显微镜(SEM)、红外光谱仪、激光粒度仪和电荷密度测定仪(PCD)对产物进行了表征。研究表明,当w(CS-8)=8%,w(APS)=0.5%,w(松香)=2%时,所制SAE无皂乳液性能优异,施胶效果良好。在SAE制备过程中添加松香作为功能性单体,能明显改善经SAE表面施胶后纸页的抗水性能。     

葡聚糖水凝胶微球的制备与表征

采用反相微乳液交联法,以葡聚糖天然高分子为原料,制备了一系列基于葡聚糖的水凝胶微球。葡聚糖通过高碘酸钠氧化进行醛基化修饰,进一步与乙二胺发生还原胺化反应进行交联;交联反应在以失水山梨酸酯类(Span 80/Tween 80)表面活性剂复配体系作为乳化剂、环己烷为油相构成的油包水型反相微乳液中进行。表面活性剂复配体系的组分配比是影响该葡聚糖水凝胶微球的粒径及形貌的重要因素,研究结果表明,随着表面活性剂复配体系的亲水亲油平衡值(HLB value)增加,微球粒径呈现先减小而后增大并基本保持不变的趋势;当该复配表面活性剂的HLB=5.27(即,m(Tween 80)/m(Span 80)=10)时,获得的葡聚糖凝胶微球粒径最小且平均粒径为(21.6±1.65)μm,粒径分布在15~28μm之间。     

双层纸浆模塑制品成型工艺影响因素的研究

目的为了改善纸浆模塑的表观性能,提高纸模制品的附加值。方法研究一种双层纸浆模塑制品的成型工艺过程,并通过正交试验研究双层纸浆模塑制品成型工艺的影响因素。结果正交试验表明,纸浆模塑制品的湿坯含水率和特种浆料的打浆度都能引起制品色差的变化,最佳条件下的色差ΔE=0.41。结论通过正交试验分别确定了3个条件因素对色差影响的主次顺序,分别为湿坯含水率、打浆度和浆料配比,并通过极差分析确定了最佳条件因素,湿坯含水率为15%,特种浆料打浆度为20°SR,外层特种浆与内层普通浆的质量配比为0.45。     

阳离子淀粉微球的合成与表征

以可溶性淀粉为原料,环己烷和水构成反相悬浮体系,Span60和Tween60为复配乳化剂,N,N'-亚甲基双丙烯酰胺(MBAA)为交联剂,采用反相悬浮聚合法合成中性淀粉微球,再用醚化剂GTA与中性淀粉微球反应,制得阳离子淀粉微球.以微球的平均粒径和溶胀度为指标,分析了不同因素对微球合成的影响.运用红外光谱、扫描电镜、粒度分析仪对产物进行了表征分析.实验结果表明,该阳离子淀粉微球结构致密、强度高,平均粒径为15.2μm,并接枝有季胺盐阳离子基团,可作为一种良好吸附载体.     

含固相淀粉的反相乳液体系稳定性研究

以液体石蜡为油相,烯类单体的水溶液为水相,Span80和OP-4为复配乳化剂,制备反相乳液。考察了乳化剂H LB值及浓度、水相体积分数Φ、单体用量及固相淀粉颗粒对乳液类型及稳定性的影响规律。实验结果显示:乳化剂H LB值对乳液类型及稳定性影响显著,在H LB=4.3~6.1范围内,能形成稳定的油包水(W/O)型乳液;乳化剂最佳浓度即其质量分数为5%~8%;Φ应小于50%;单体将导致反相乳液稳定性降低;固体淀粉的存在有利于形成W/O型反相乳液,并且能使反相乳液体系的稳定性明显提高。     

含固相淀粉的反相乳液体系稳定性研究

以液体石蜡为油相,烯类单体的水溶液为水相,Span80和OP-4为复配乳化剂制备反相乳液.考察了乳化剂HLB值及浓度、水相体积分数Φ、单体用量及固相淀粉颗粒对乳液类型及稳定性的影响规律.实验结果显示:乳化剂HLB值对乳液类型及稳定性影响显著,在HLB=4.3～6.1范围内,能形成稳定的油包水(W/O)型乳液;乳化剂最佳质量分数为5%～8%;Φ应小于50%;单体将导致反相乳液稳定性降低;固体淀粉的存在有利于形成W/O型反相乳液,并且能使反相乳液体系的稳定性明显提高.     

微乳液法制备硫化银纳米颗粒及抗磨性能

在两种W/O微乳液体系中制备了Ag₂S纳米颗粒, 用透射电子显微镜(TEM)、X射线粉末衍射仪(XRD)对其形貌和结构进行了表征. 结果表明, 在异辛烷/油酸钠/ 正戊醇/ 水溶液和液体石蜡/Span 80-Tween 80/正丁醇/水溶液两种微乳液体系中所制备的Ag₂S纳米颗粒均具有单斜晶型结构, 颗粒粒度分布均匀, 无团聚现象, 平均粒径分别为18和5nm. 在四球长时抗磨损试验机上考察了分散于液体石蜡中Ag₂S纳米颗粒的抗磨性能, 通过扫描电子显微镜(SEM) 对钢球磨斑表面进行了形貌观测. 结果显示, 在液体石蜡/Span80-Tween80/正丁醇/水溶液体系中制备的Ag₂S纳米颗粒可以稳定分散在液体石蜡中, 具有较好的抗磨性能, 并且能显著提高基础油的承载力.     

P(VAc-MMA-DM)阳离子聚合物乳液的合成及其在造纸增强中的应用

以醋酸乙烯酯(VAc)、甲基丙烯酸甲酯(MMA)和甲基丙烯酸二甲胺乙酯(DM)为原料,采用无乳化剂乳液聚合法合成出了一系列VAc-MMA-DM阳离子共聚物乳液,测定了此乳液的转化率和稳定性,找到了合成最稳定且转化率最高的VAc-MMA-DM阳离子共聚物乳液的配方和条件;由电镜测得此乳液为球形粒子,粒径约为0.1 μm.将VAc-MMA-DM阳离子共聚物乳液加到竹浆或纸浆中,通过对纸张的环压强度、耐破度、撕裂度等的测定,发现当乳液的用量为1.0%时,其增强性能最好.     

Effect of process parameters on surfactant-based synthesis of hydroxy sodalite particles

Hydroxy sodalite (HS) particles of different morphologies were synthesized by non-ionic surfactant-based water-in-oil (w/o) emulsion technique at 90 °C. Span 80 (HLB: 4.3), Span 20 (HLB: 8.6), and Tween 80 (HLB: 15) were used as nonionic surfactants. The effects of different surfactants as well as concentration and time variations of Span 80 on the synthesized particles were studied for understanding their crystallization and microstructural behaviors. The synthesized particles were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FESEM). FTIR and XRD studies confirmed the formation of HS particles under all the varied conditions. Urchin-shaped particles obtained from Span 80 disappeared with the formation of agglomerated particles consisting of rod-like grains and microspheres, and stone-like agglomerated particles from Span 20 and Tween 80-derived emulsions respectively with 1 wt.% concentration each in n-heptane. On the other hand, flower-like and nest-like morphologies of HS particles were obtained in presence of 1 wt.% Span 80 of the emulsion at 90 °C for 5 and 15 h, respectively.     

纸浆模塑模具的制作材料及其性能

针对制作纸浆模塑模具用材料的基本要求,介绍了各种制模材料的特性、规格及其对纸浆模塑生产的影响,综述了各种材料制作纸模模具的方法及其应用。     

不合格品乳化炸药破乳剂及破乳条件的选择

利用Op 10、Tween 80、十二烷基苯磺酸钠、Span 20和石油醚对乳化炸药进行破乳,并且利用电导率及硝酸铵(AN)的析出率来表示破乳剂破乳效果的好坏。通过分析这些破乳剂破乳后的现象及测定电导率和AN的析出率,发现Op 10、Tween 80与石油醚的破乳效果较好,而且破乳条件比较好把握。该研究为今后工业处理废乳化炸药提供了参考。     

Nonionic surfactant vesicles (niosomes) of cytarabine hydrochloride for effective treatment of leukemias: encapsulation, storage, and in vitro release

Niosome vesicles of cytarabine hydrochloride were prepared by a lipid hydration method that excluded dicetylphosphate. The sizes of the vesicles obtained ranged from 600 to 1000 nm, with the objective of producing more blood levels in vivo. The study of the release of drug from niosomes exhibited a prolonged release profile as studied over a period of 16 hr. The drug entrapment efficiency was about 80% with Tween 80, Span 60 and Tween 20; for Span 80, it was 67.5%. The physical stability profile of vesicular suspension was good as studied over a period of 4 weeks.     

Nonionic Surfactant Vesicles (Niosomes) of Cytarabine Hydrochloride for Effective Treatment of Leukemias: Encapsulation,Storage, and In Vitro Release

Niosome vesicles of cytarabine hydrochloride were prepared by a lipid hydration method that excluded dicetylphosphate. The sizes of the vesicles obtained ranged from 600 to 1000 nm, with the objective of producing more blood levels in vivo. The study of the release of drug from niosomes exhibited a prolonged release profile as studied over a period of 16 hr. The drug entrapment efficiency was about 80% with Tween 80, Span 60 and Tween 20; for Span 80, it was 67.5%. The physical stability profile of vesicular suspension was good as studied over a period of 4 weeks.     

纸浆模塑托盘结构强度的实验测试分析

实验研究了纸浆模塑托盘结构的力学性能,测试分析了纸浆模塑托盘的承载能力,包括纸浆模塑托盘支腿单元结构的抗压能力,纸浆模塑托盘整体结构的抗压能力、抗弯性能。结果表明:纸浆模塑托盘的抗弯能力相对较弱,实验样品的平均抗弯载荷为1.32 kN;从抗压能力来看,纸浆模塑托盘整体承载能力与各个支腿承载能力的总和相接近;纸浆模塑托盘整体结构的抗压承载能力可达47.80 kN。     

咪唑啉型复配缓蚀剂对20钢在高含CO2油田污水中缓蚀行为影响的研究

利用缓蚀剂成膜试验和失重试验研究了咪唑啉型复配缓蚀剂对20钢在高含CO2油田污水中的缓蚀行为.成膜试验结果表明,咪唑啉型缓蚀剂与TXP-10、乌洛托品、异丙醇复配后,大大提高了成膜的完整性.70℃和90℃时,咪唑啉酰胺和松香咪唑啉季铵盐缓蚀剂复配后,有利于提高缓蚀效率;120℃时,咪唑啉酰胺缓蚀剂分子分解,而松香咪唑啉...     

机械活化淀粉反相乳液聚合动力学及机理探讨

以过硫酸铵为引发剂,研究了经机械活化预处理的玉米淀粉与丙烯酰胺在反相乳液体系中的接枝共聚反应动力学,分别考察了引发剂浓度、单体浓度、淀粉乳浓度和乳化剂浓度等对表观聚合速率的影响。结果表明,在本实验考察范围内的动力学关系式为Rp∞[I]0.84[M]1.12[St]1.07[E]0.54。推导并验证了该反应的表观动力学方程和反应机理,双基终止与单基终止过程同时存在,实验结果与理论推导基本符合。     

Screening of formulation variables for the preparation of poly(epsilon-caprolactone) nanocapsules containing the local anesthetic benzocaine

In this work we describe the screening of four parameters in the preparation, by nanoprecipitation, of poly(epsilon-caprolactone) nanocapsules, used as a drug carrier system for the local anesthetic, benzocaine. A 2(4-1) factorial experimental design was used to study the influence of four different independent variables (polymer, oily phase, Span 60 and Tween 80) on nanocapsule characteristics (size, polydispersion index, zeta potential) and drug loading capability. Best results were obtained using an aqueous formulation comprising 100 mg of polymer, 200 mg of oily phase, 40 mg of Span 60 and 60 mg of Tween 80 in a final volume of 10 mL which produced a colloidal system with particle size of 188 nm, zeta potential -32 mV, polydispersion index 0.07, and benzocaine association efficiency > 87%. These findings open the way for future clinical studies using such formulations.