The two-dimensional one-component plasma in a doubly periodic background: Exact results

We revisit the equilibrium classical statistical mechanics of the two-dimensional one-component plasma, for the special value =2 of the coupling constant. Using a new method, we find that the model is solvable (then-body densities can be explicitly computed) for a larger class of inhomogeneous backgrounds. In particular, we can deal with a doubly periodic background; this is a classical model for a crystal made of fixed ions and mobile electrons. At =2, this system is conducting: the correlations have a fast decay, and the Stillinger-Lovett screening sum rule is obeyed.     

Synthesis of lightly crosslinked zwitterionic polymer‐based bioinspired adhesives for intestinal tissue sealing

In this report, we have developed a new bioinspired medical adhesive capable of providing a leak‐proof barrier for application to intestinal anastomoses. The newly synthesized adhesive is a terpolymer possessing three different repeating units: (1) A zwitterionic polymer, poly(sulfobetaine methacrylate) (polySBMA), for increased hydrophilicity and biocompatibility, (2) a 3,4‐dihydroxy‐L‐phenylalanine (DOPA) segment which contains the catechol group, and (3) poly(ethylene glycol) dimethacrylate (PEGDMA) for light crosslinking, which will be used to strengthen the polymer adhesion properties by providing debonding resistance. The chemical structure of the terpolymer, poly(N‐methacryloyl‐3,4‐dihydroxyl‐L‐phenylalanine‐co‐sulfobetaine methacrylate‐co‐poly(ethylene glycol) dimethacrylate) (poly(MDOPA‐co‐SBMA‐co‐PEGDMA)), synthesized following a convenient and reproducible radical polymerization was clearly confirmed by ¹H NMR. The terpolymer adhesive displayed the optimal adhesion properties when containing 1.5–2.5 mol % of crosslinker, PEGDMA, according to the measured maximum adhesion strength and work of adhesion, characterized by lap shear strength tests utilizing porcine skin. The adhesive did not show cytotoxicity when tested with human embryonic kidney (HEK293A) cells. Ex vivo anastomosis experiments using porcine intestine demonstrated that the new poly(MDOPA‐co‐SBMA‐co‐PEGDMA) is a promising biomedical adhesive which successfully prevents leakage from the sutured intestinal tissue. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1564–1573     

Bio-based tri-functional epoxy resin (TEIA) blend cured with anhydride (MHHPA) based cross-linker: Thermal,mechanical and morphological characterization

A novel renewable resource based tri-functional epoxy resin from itaconic acid (TEIA) was blended with petroleum based epoxy resin (DGEBA) and fabricated at different ratios. Then, it was by thermally cured with methylhexahydrophthalic anhydride (MHHPA) in presence of 2-methylimidazole (2-MI) catalyst. The tensile, modulus, strength of virgin epoxy resin (41.97 MPa, 2222 MPa) increased to 47.59 MPa, 2515 MPa, respectively, with the addition of 30% of TEIA. The fracture toughness parameter, critical stress intensity factor (K_IC) revealed enhancement of toughness in the TEIA bio-based blends system. The thermomechanical properties of TEIA (tri-functional epoxy resin from itaconic acid) modified petroleum-epoxy networks were investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The fracture morphology was also studied by the scanning electron microscopy and atomic force microscopy respectively.     

A functional relation among the pair correlations of the two-dimensional one-component plasma

We map the classical two-dimensional one-component plasma of charged particles with coupling constant an even positive integer onto a one-dimensional fermionic system. We then show that, in the thermodynamic limit of the fluid regime, translational invariance of the two-body density implies an infinite sequence of interrelations among the coefficients of its short-distance expansion. The existence of these sum rules turns out to be related to a general symmetry of the Coulomb system, providing a functional relation for the two-body density for arbitrary coupling .     

Effect of Glass Transition Temperature of Pressure Sensitive Adhesives on Light Leakage in LCD Panel

Pressure-sensitive adhesives (PSA), which mainly are made of acrylic polymers, have been used to fix optical films to liquid crystal display (LCD) cells to prevent contraction or expansion of the optical film under high temperature and high humidity conditions, while residual stress on the polarizing film is generated and light-leakage results from it in the peripheral area of an LCD panel. In this work, we prepared two different kinds of PSAs and tested light leakage with respect to T_g, verifying that T_g would have an effect on light leakage. We calculated their T_g values using the Fox equation and investigated them by DSC. Rheological properties of the PSAs were also acquired by a rotational rheometer which confirm the relation between T_g and dynamic moduli (G′ and G″). It was found that the higher the T_g, the less is an amount of light leaked.     

Preparation and characterization of organic–inorganic hybrids and coating films from 3‐methacryloxypropylpolysilsesquioxane

3‐Methacryloxypropylpolysilsesquioxane (MA‐PS) was prepared by acid‐ or base‐catalyzed hydrolytic polycondensation of 3‐methacryloxypropyltrimethoxysilane (MAS). MA‐PS coating film was prepared by dip‐coating on organic, metal and inorganic substrates, including poly(ethylene terephthalate), aluminum, stainless steel, and glass. The coating films on poly(ethylene terephthalate) and glass showed high adhesive strength. The hardness of coating films increased with increasing heat treatment temperature, whereas they decreased with increasing H₂O/MAS molar ratio. The refractive index of coating films increased with increasing heat treatment temperature. In addition, flat and transparent free‐standing films (0.24–0.27 mm thickness) were prepared from MA‐PS that were crack‐free after heat treatment at 1000 °C. Copyright © 2001 John Wiley & Sons, Ltd.     

Dendrimer-based Hydrogels with Controlled Drug Delivery Property for Tissue Adhesion

In recent years,the hydrogel-based tissue adhesives have been extensively investigated for their excellent biocompatibility and the ability to be administered directly within the adherent tissue.To meet the requirement for more controllable release in various physiological settings,the components of hydrogel adhesive should be more precisely tailored.In this work,the POSS-ace-PEG hydrogel adhesive was fabricated with the polyacetal dendrimer G1'-[NH3Cl]16 and poly(ethylene glycol) succinimidyl carbonate (PEG-SC) due to the regular peripheral amino structure of G1'-[NH3Cl]16.Rheological and adhesion tests demonstrated that the hydrogel adhesive had good mechanical and adhesive properties,which could effectively adhere to the pigskin and severed nerves.Moreover,the tissue adhesive exhibited good stability under neutral conditions and the rapid degradation under acidic conditions,allowing for the release of doxycycline hydrochloride (DOX) drug in response to pH.Together,these results suggested that the POSS-ace-PEG adhesive had the potential to provide an alternative to tissue adhesives for applications in pathological environments (inflammation,tumors,etc.).     

木质素磺酸盐基胶黏剂的合成与表征

以双氧水(H2O2)-硫酸亚铁(FeSO4)为氧化还原引发剂,丙烯酸(AA)和马来酸酐(MAH)为单体,采用原位一步法制备了宽分子量分布的P(MAH-co-AA)。通过测定P(MAH-coAA)和木质素磺酸盐(LS)缩聚反应产物的凝胶含量,研究了P(MAH-co-AA)中单体组成、胶黏剂酸度和添加三乙醇胺(TEA)等因素对交联的影响,比较了木质素磺酸钠(LSS)和木质素磺酸铵(LSA)两种LS的反应活性。结果表明:木质素磺酸盐能代替部分多元醇与共聚物制备低成本无甲醛型木材用胶黏剂;提高共聚物P(MAH-co-AA)中MAH含量、胶黏剂酸度及采用LSA均能提高固化交联的程度。     

基于邻苯二酚的可降解黏合剂的制备及表征

以氨基化聚乙二醇(mPEG-NH2)为大分子引发剂,制备了基于邻苯二酚[如3,4-二羟基苯丙酸(DHPPA)和3,4-二羟基苯丙胺即多巴胺(Dopamine)]的仿生黏合剂聚乙二醇单甲醚-聚赖氨酸-g-3,4-二羟基苯丙酸[mPEG-b-P(LL-g-DHPPA)]和聚乙二醇单甲醚-聚谷氨酸-g-3,4-二羟基苯丙胺[mPEG-b-P(LG-gDopamine)].用核磁共振波谱(NMR)、傅里叶变换红外光谱(FTIR)和凝胶渗透色谱(GPC)等方法表征了mPEG-b-P(LL-g-DHPPA)和mPEG-b-P(LG-g-Dopamine)的结构.mPEG-b-P(LL-g-DHPPA)和mPEG-b-P(LG-gDopamine)的接枝度分别为30%和28.6%,即每个聚合物分子链上分别接上了13.5个DHPPA单体和13个Dopamine单体.剪切强度测试结果表明,mPEG-b-P(LL-g-DHPPA)更有利于黏合剂的固化并能提高黏合剂的内聚强度.