单宁胶用PUF树脂的制备工艺与结构和交联性能关系的研究

提出了一种单宁胶用ＰＵＦ树脂的制备方法。用＾１３ＣＮＭＲ研究了制备条件对ＰＵＦ树脂组分、结构和交联性能的影响。压板试验表明ＰＵＦ树脂配制单宁胶时，只有折合甲醛值大于１０％，压制的胶合板才能符合室外级板的强度要求。用ＤＳＣ研究了固化温度对该单宁胶固化程度的影响。     

多元羧酸与木材的交联反应机理——五元环酸酐反应中间体的FTIR波谱特征

该研究采用一类新型的、水溶性的、无毒害、无污染的以多元羧酸类化合物为酯化剂,以无机盐和含氮化合物为催化剂的非甲醛系试剂为交联体系,利用ＦＴＩＲ分析多元羧酸类化合物与木材组分的交联反应过程的波谱特征。依据反应对交联剂立体构型的选择性、反应中间体模型物与木材的交联反应和交联反应中间体的波谱特征实验结果,证实了交联反应中间体的存在,推证这一酯化反应的历程是经历两步反应的机理,首先多元羧酸中相邻羧基的羟基之间脱水形成五元环酸酐中间体,然后木材的羟基与酸酐发生亲核取代反应形成酯。而不是经历了通常的羧酸与醇直接脱水形成酯的四面体中间物的过程。     

鱼鳞胶原-壳聚糖止血海绵的制备工艺

以罗非鱼Tilapia mossambica鱼鳞为原料,经低温酶解提取鱼鳞Ⅰ型胶原,将鱼鳞Ⅰ型胶原与壳聚糖进行混合交联,冻干后制成胶原-壳聚糖止血海绵。以止血海绵的密度、吸水倍数、保水率、透气率和止血时间为指标,通过单因素实验和正交试验优化获得最佳的制备工艺:胶原与壳聚糖配比7∶3、制备液总浓度1.4%、交联剂添加量0.015%。在该最佳工艺下制备的止血海绵密度为22.95mg/cm3、吸水倍数为45.34、保水率为55.83%、透气率为46.36%、止血时间为68.0s,呈蜂窝状多孔结构,具有优良的持水性和透气性。     

Synthesis and Properties of Fumaropimaric Acid Modified RTV Silicone Rubber北大核心CSCD

Fumaropimaric acid modified aminopropyltriethoxysilane(FA) was prepared by derivative reaction with rosin as raw material and the structure of the product was confirmed by FT-IR, 1H NMR and 13C NMR. Fumaropimaric acid modified room temperature vulcanized(RTV)silicone rubber was prepared by the dealcoholization condensation reaction of crosslinking agent(FA) and hydroxyl end-blocked dimethylsiloxane(PDMS). And the effects of hydrogenated phenanthrene ring of rosin on the morphology, mechanical and thermal properties of fumaropimaric acid modified RTV silicone rubber were studied, it was found that fumaropimaric acid modified RTV silicone rubber had better the mechanical and thermal properties compared to the unmodified silicone rubber. The tensile strength and elongation at break were 1.22 MPa and 315%; and The 10% mass loss temperature increased to 472 ℃ (SRFA-1), the greatest rate of mass loss temperature increased to 569 ℃, and the residual rate was 3.88%, respectively. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved.     

Durable press finish of cotton via dual curing using UV light and heat

Continuous photografting/crosslinking of polyethyleneglycol dimethacrylate oligomers onto cotton using a water-soluble benzophenone photoinitiator was investigated. Photografting increased with increasing irradiation dose, oligomer concentration and photoinitiator concentration. Maximum grafting efficiency of DM 400 and 600 were 83% and 79%, respectively. The photografting increased the wrinkle resistance of cotton implying surface crosslinking of cotton. Both surface crosslinking and bulk crosslinking of cotton were accomplished via dual curing of a mixed formulation containing both a thermally curable component (BTCA/SHP) and a UV-curable component. The wrinkle resistance of the crosslinked cotton was found to be higher when cured by thermal curing after UV curing rather than by UV curing after thermal curing due to the facile post-polymerization of the UV active component. The presence of crosslinks in the dually crosslinked cotton was verified with FT-IR and thermogravimetric analysis.     

三聚氰胺—甲醛与木材的交联作用

为了研究木材压密化处理过程中交联试剂与木材的作用机理，以大青杨木材为试样，分离制得综纤维素、纤维素、α－纤维素、木质素和半纤维素，并分别与三聚氰胺－甲醛反应，测定了不同化学组分与交联剂作用的活性顺序及其分布。结果表明：三聚氰胺－甲醛与大青杨木材细胞壁组分的反应活性顺序为：木质素＞半纤维素＞综纤维素＞α－纤维素＞纤维素。还采用红外光谱（ＩＲ）对交联作用前后的综纤维素、纤维素和木质素的化学结构变化进行了分析，从而定性确定了交联化处理木材的主要官能团变化。关键词     

The effects of electrical discharge on the mechanical properties of <Emphasis Type="Italic">Bombyx mori</Emphasis> silk fibroin

Bombyx Mori is a representative of natural fibers which is known for its mechanical stability. In this study, electrical discharge of the fibers exposed to different voltages for certain periods was examined and mechanical lifetime was measured and also the structure parameters U _o and γ were calculated. We observed that crosslinks might be formed at the silk fibers exposed to high voltages and as a result, fibers become more resistant to mechanical effects.     

EVA—异氰酸酯动态粘弹性分析

本文采用粘弹性测定仪（Ｖｉｂｒｏｎ，ＤＤＶ－Ⅱ型）研究醋酸乙烯酯——乙烯共聚乳液（ＥＶＡ）——异氰酸脂（ＩＣ）的动态粘弹性，并计算了ＥＶＡ／ＩＣ间的交联密度与温度的关系。研究结果表明，ＥＶＡ与ＩＣ间的交联密度与温度密切相关，并与胶层的抗拉强度及耐温性能相关。     

Effect of glycols and catalysts on cotton fabrics treated with glyoxal

The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA) and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition.     

蔗糖-三聚氰胺-甲醛共缩聚树脂胶黏剂的合成研究

以蔗糖、三聚氰胺、甲醛为原料,在碱性条件下合成了外观为黄色、透明、均一、无沉淀且水溶性好的蔗糖-三聚氰胺-甲醛(SMF)共缩聚树脂木材胶黏剂。采用均匀试验设计对合成反应体系的蔗糖、交联剂用量和甲醛与三聚氰胺的摩尔比进行了优化,通过正交试验设计对桉树胶合板热压工艺参数进行了优化。结果表明:最佳合成条件为:蔗糖与三聚氰胺的摩尔比为0.7,甲醛与三聚氰胺的摩尔比为2.7,交联剂用量为树脂的0.33%;桉树胶合板最佳胶合工艺参数为:双面施胶量为340g/m~2、热压压力为0.9MPa、热压温度为150℃、热压时间为60s/mm。