马来松香聚甘油酯的合成及性能研究

马来松香与聚甘油反应,合成了一种非离子表面活性剂马来松香聚甘油酯(PGMRE)。对产品结构进行了红外光谱分析,测定了产品的表面物理化学性能,合成产品临界表面张力为39 9mN/m～46 0mN/m,临界胶束浓度在9 4×10-4mol/L～2 3×10-3mol/L数量级,钙皂分散指数是9 0%～26 7%,与松节油之间的界面张力为8 0mN/m～13 9mN/m,对松节油乳化力为38s～100s,泡沫性能是11mm～65mm,润湿力为70s～102s。系统研究了甘油聚合度对产品表面物理化学性能的影响。并与聚甘油硬脂酸酯(PGSE)和聚甘油异硬脂酸酯(PGISE)的表面物理化学性能进行了比较。结果表明PGMRE是一种性能优良的非离子表面活性剂,可作为乳化剂、破乳剂和缓蚀剂等使用。     

从粗甘油蒸馏残渣中回收聚合甘油

粗甘油蒸馏过程中,部分甘油在高温下发生聚合,聚合甘油沸点很高,在通常真空蒸馏条件下无法蒸出而留在残渣中。实验证明,甘油蒸馏残渣经过化学处理除杂后,通过离子交换,可以回收得到色泽（Hazen）100以下的甘油质;采用短程蒸馏（Short-path distillation）技术,可以得到高质量的甘油和聚合甘油。回收率为总甘油质的80％以上。此外,还对皂化甘油蒸馏操作提出了建议,以提高甘油蒸馏得率和聚合甘油的富集。     

Double emulsions of water-in-oil-in-water stabilized by α-form fat microcrystals. Part 1: Selection of emulsifiers and fat microcrystalline particles

Double emulsions are commonly stabilized by monomeric and/or polymeric emulsifiers. Pickering stabilization by solid particles such as colloidal microcrystalline cellulose has been mentioned only once as a possible technique to stabilize the external interface of the water-in-oil-in-water emulsion. No further work was carried out exploring this option. The present study shows that solid microcrystalline fat particles of α-form are capable of adsorbing at the water-oil interface and, together with other hydrophobic emulsifiers, can stabilize water-in-oil (W/O) emulsions. The crystals must be submicron in size in order to effectively adsorb and arrange at the interface. Large crystals do not fit and were found to flocculate as free crystals in the continuous oil phase. The α-form crystals can be obtained by flash-cooling saturated triglycerides in vegetable oils in the presence of emulsifiers, such as polyglycerol polyricinoleate (PGPR), that stabilize the dispersion and serve as α-tending crystal structure modifiers. It was assumed that PGPR also serves as a cross-linker or bridge between the crystalline fat particles and the water, and facilitates the anchoring of the fat particles in the oil phase in one direction while dangling itself in the water phase. The double emulsion droplets prepared with these W/O emulsions are relatively large in size (6–18 μm), but stable to coalescence. The marker (NaCl) does not seem to release with time, suggesting that the fat particles form microcapsules on the water interface, totally sealing the water from releasing its addenda. The systems seem to have a significant potential for food emulsions.     

Graphene-Assisted Synthesis of 2D Polyglycerols as Innovative Platforms for Multivalent Virus Interactions

2D nanomaterials have garnered widespread attention in biomedicine and bioengineering due to their unique physicochemical properties. However, poor functionality, low solubility, intrinsic toxicity, and nonspecific interactions at biointerfaces have hampered their application in vivo. Here, biocompatible polyglycerol units are crosslinked in two dimensions using a graphene-assisted strategy leading to highly functional and water-soluble polyglycerols nanosheets with 263 ± 53 nm and 2.7 ± 0.2 nm average lateral size and thickness, respectively. A single-layer hyperbranched polyglycerol containing azide functional groups is covalently conjugated to the surface of a functional graphene template through pH-sensitive linkers. Then, lateral crosslinking of polyglycerol units is carried out by loading tripropargylamine on the surface of graphene followed by lifting off this reagent for an on-face click reaction. Subsequently, the polyglycerol nanosheets are detached from the surface of graphene by slight acidification and centrifugation and is sulfated to mimic heparin sulfate proteoglycans. To highlight the impact of the two-dimensionality of the synthesized polyglycerol sulfate nanosheets at nanobiointerfaces, their efficiency with respect to herpes simplex virus type 1 and severe acute respiratory syndrome corona virus 2 inhibition is compared to their 3D nanogel analogs. Four times stronger in virus inhibition suggests that 2D polyglycerols are superior to their current 3D counterparts.     

Reactive core/shell type hyperbranched blockcopolyethers as new liquid rubbers for epoxy toughening

Novel reactive core/shell-type hyperbranched blockcopolyethers were tailored as new class of liquid rubbers useful as flexibilizers and toughening agents of anhydride-cured epoxy resins. Anionic ring-opening polymerization of glycidol onto a six-arm star poly(propylene oxide-block-ethylene oxide) afforded hyperbranched polyether cores as macroinitiators for propylene oxide graft copolymerization. The hydroxy end groups of the resulting polyether-polyols have been modified in order to prepare stearate, hydroxy benzoate and epoxy derivatives. The modification afforded reactivity and polarity design which has been the key to improved blend performance with epoxy resins. In comparison to conventional hyperbranched epoxy-terminated polyesters, the influence of molecular architectures on thermal, mechanical and morphological properties of hexahydrophthalic acid anhydride-cured bisphenol-A diglycidylether was examined. As a function of polarity and reactivity design, it was possible to control phase separation and to vary mechanical properties from highly flexible to stiff and tough.     

Polyglycerol‐Dendronized Perylenediimides as Stable,Water‐Soluble Fluorophores

The synthesis and photophysical properties of water‐soluble, fluorescent polyglycerol‐dendronized perylenediimides 1–4 are reported. The polyglycerol dendrons, which are known to be highly biocompatible, are found to confer high water‐solubility on the perylenediimide in aqueous media while retaining its excellent fluorescent properties. Furthermore, intramolecular crosslinking of the polyglycerol dendrons using the ring‐closing metathesis reaction not only enhances the photostability but also reduces the size of perylenediimide‐cored dendrimers. The permeability of the various dendritic shells is probed using heavy metal ion quenchers and compared to non‐dendritic but water‐soluble perylenediimide 5 .     

Stabilization of water-in-oil emulsions by submicrocrystalline α-form fat particles

The results presented in this study confirm previous knowledge and stress the need for both hydrophobic emulsifiers and submicronial fat particles to stabilize water-in-vegetable oil emulsions. It was demonstrated that polyglycerol polyricinoleate (PGPR) is superior to glycerol monooleate and/or lecithin, but is incapable of stabilizing these fluid emulsions for sufficient storage periods. Fluid emulsions, unlike margarine, exhibit high droplet mobility and are susceptible to flocculation and coalescence. It was also demonstrated that submicronial α-form crystals of hydrogenated fat can be obtained in the oil phase by the flash-cooling process. The crystals are homogeneously almost mono-dispersed and exhibit insufficient stability against flocculation and phase separation. The use of an emulsifier (PGPR) in the fat crystallization process was very helpful in decreasing the aggregation and flocculation processes. The α-form (mixed with β′-form) submicronial crystals can stabilize water-in-oil emulsions only in the presence of food emulsifiers, provided the concentration of tristearin is limited to 1.0–2.0 wt% (to prevent phase separation and high viscosity) and the PGPR is added at sufficient concentrations (PGPR/tristearin ratio of 2.0 or more). Ideally stable (for over 6–8 wk) fluid emulsions can be formed in systems composed of fat submicrocrystalline hydrophilic particles and food-grade emulsifiers. These water-in-oil emulsions can serve as the basic preparation for any food-grade water-in-oil-in-water double emulsion.     

Polymerization of ethyl acrylate using hyperbranched polyglycerol with multi‐RAFT groups as chain transfer agent

Surfacing hydroxyl groups of hyperbranched polyglycerol (PG) were transformed into trithiocarbonates (TTC), an efficient multi radical addition‐fragmentation transfer (RAFT) agent, to mediate the polymerization of ethyl acrylate (EA) under controllable conditions, and PG with multiarm PEA was obtained. In this system, PG was a part of Z groups, and trithiolcarbonates were bonded directly to the PG, whereas the growing PEA macroradical was detached. The molecular weight and the molecular weight distribution of the products were in the range of 1.05–3.24 × 10⁴ g/mol and 1.28–1.42, respectively, when the concentration ratio of EA to PG‐TTC was 39.8. The number of the PEA arms was about 16. It was found that the measured molecular weights of the products were deviated from the theoretical value, and the molecular weight distribution was broadened with the conversion due to the termination between the leaving macroradicals. The final and the intermediate products were characterized by NMR in detail. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2203–2209, 2006     

碱金属氢氧化物及其碳酸盐均相催化甘油低聚反应的研究

以碱金属氢氧化物及其碳酸盐为均相催化剂,在不同的反应条件下,考察了该类催化剂对甘油低聚反应的催化性能.通过高效液相色谱对反应产物进行了定量分析,研究了甘油转化率、反应时间和甘油聚合态分布之间的关系.结果表明,碱金属氢氧化物与碱金属碳酸盐均具有较高的催化活性,甘油转化率在80%左右时,产物中二聚和三聚甘油的选择性为63%～71%,其中环状二聚甘油的含量随甘油转化率的升高而增加.