Continuous Flow Fabrication of Block Copolymer–Grafted Silica Micro‐Particles in Environmentally Friendly Water/Ethanol Media

Polymer‐grafted inorganic particles (PGIPs) are attractive building blocks for numerous chemical and material applications. Surface‐initiated controlled radical polymerization (SI‐CRP) is the most feasible method to fabricate PGIPs. However, a conventional in‐batch reaction still suffers from several disadvantages, including time‐consuming purification processes, low grafting efficiency, and possible gelation problems. Herein, a facile method is demonstrated to synthesize block copolymer–grafted inorganic particles, that is, poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMEMA)‐b‐poly(N‐isopropylacrylamide) (PNIPAM)–grafted silica micro‐particles using continuous flow chemistry in an environmentally friendly aqueous media. Immobilizing the chain transfer agent and subsequent SI‐CRP can be accomplished sequentially in a continuous flow system, avoiding multi‐step purification processes in between. The chain length (MW) of the grafted polymers is tunable by adjusting the flow time or monomer concentration, and the narrower molar mass dispersity (Р< 1.4) of the grafted polymers reveals the uniform polymer chains on the particles. Moreover, compared with the in‐batch reaction at the same condition, the continuous system also suppresses possible gelation problems.     

Recycling of multilayer packaging using a reversible cross-linking adhesive

Plastic-based multilayer packaging has an important function on the packaging market, but is currently not recyclable as the polymer layers used are usually thermodynamically immiscible. This work therefore follows the approach to prepare separable multilayer packaging using a packaging adhesive modified with thermally unstable adducts, and proposes a corresponding recycling process. For this purpose, typical multilayer structures (polyethylene (PE)// polyethylene terephtalate (PET), PET//aluminum, and PE//aluminum) were prepared by curing furan-/maleimide-functionalized polyurethane (PU)-prepolymers with a three-functional cross-linking agent. Adhesions of up to over 3N per 15 mm test specimen were measured or substrate failures of PET films were observed. However, heating in dimethylsulfoxide, the retro-Diels–Alder reaction takes place and the cross-linked adhesive turns thermoplastic and dissolves in the solvent. Thus, the laminate separates and the pure PE, PET, and aluminum foils can be recovered without any PU residue.     

LaZSM5-Al-Mg催化剂上乙烯与甲苯烷基化制对甲基乙苯

以LaZSM5沸石为基质,添加铝和镁的氧化物所制得的择形催化剂,可大大提高乙烯与甲苯烷基化制甲基乙苯中对甲基乙苯选择性。考察了稀释气和反应产物的添加对烷基化反应的影响。失活后的催化剂可烧炭再生。     

一种基于三次样条函数求离子浓度的自动算法

本文提出了一种用三次样条函数模拟双次标准加入法测量方程，直接求解离子浓度的自动算法。比较了三咱不同边界条件下用要池数计算离子浓度的结果。造出节点区间两极端点的二阶导数为零时的三次样条函数为最佳模拟函数。并讨论了该方法在实际分析中误差的来源及消除办法。经对一系列文献数据的验算对比，表明本法完全可代替传统的迭代法和查图法，且能方便地设置在智能化的电位分析系统中。     

新型硅蜡乳液的制备

将蜂蜡用复合乳化剂乳化时加入自制的乳化助剂，制得稳定的蜡乳液，将该乳液与羟基蛙油乳液复配，制得乳白色略带蓝光硅蜡乳液，该硅蜡乳液用于绵羊服装革作顶层手感改善剂，除了获得油润的蜡感和滑爽感之外，还使成革具有抗菌和抗静电作用。     

Al2O3对镁铬耐火材料致密化的影响

为了提高镁铬耐火材料的烧结性能,通过考察气孔率、体积密度和常温耐压强度与Al2O3加入量之间的关系,讨论了Al2O3添加剂对两种不同镁铬耐火材料致密化的影响.结果表明,镁铬耐火材料的骨料不同,Al2O3对其烧结性能和致密化的影响也不一样.     

微絮凝接触过滤处理低浊度含藻水的研究

通过现场试验，对微絮凝过滤处理生活用水所带来的一系列问题进行了详细、科学的分析，在大量试验数据基础上对产生问题的原因进行了研究并取得了初步结论。在此基础上，提出了改进措施，取得了实效。     

迭加与量化水印嵌入方案的比较及量化参数优化

分别研究了迭加法和量化法的隐蔽性和稳健性，并且提出了量化调制水印方案中的参数优化方法。对两类方法的分析比较表明，迭加法适用于在高频分量嵌入水印，而量化法适用于在低频分量嵌入水印。并以实验验证了这一结论。     

Influence of Zirconium Addition on Magnetic Properties and Temperature Coefficient for Nanocomposite Nd10Fe78.5-xCo5ZrxB6.5 Magnets

The influence of Zr addition on magnetic properties and temperature coefficient for nanocomposite Nd10Fe78.5-xCO5ZrxB6.5 (x=0~4) bonded magnets was investigated. It was found that the room-temperature magnetic properties were remarkably improved with Zr addition due to the grain refinement and increasing volume fraction of the hard magnetic phase. The optimal magnetic properties of Jr=0.689T, iHc=769.4kA·m-1 and (BH)max=84kJ·m-3 were obtained for 2.5% Zr addition. The temperature coefficient of remanence (α) increases slightly and the temperature coefficient of coercivity (β) decreases obviously with increasing Zr content for nanocomposite Nd10Fe78.5-xCo5ZrxB6.5 (x=0~4) bonded magnets.     

Modelling of addition polymerization processes — Free radical,ionic, group transfer,and ziegler–natta kinetics

A brief review of addition polymerization processes is presented with a summary of the key characteristics classified by kinetic mechanism (free-radical, anionic, cationic, group transfer, or Ziegler–Natta), phase behavior, and reactor type. A practical approach to modelling in the industrial R & D environment is discussed in terms of a CAD package for polymerization processes.