苯氧基二氯均三嗪改性纤维素的合成与水解

以三聚氯氰(TCT)、苯酚为原料,合成2,4-二氯-6-苯氧基-1,3,5-三嗪衍生物(PHCT);通过红外光谱和质谱表征其结构。用PHCT对纤维进行修饰,并将修饰后的微晶纤维素在8%(wt)H2SO4中、130℃下水解5 h,研究PHCT用量对纤维素水解性能和结晶结构的影响;实验结果表明,经PHCT改性的纤维素水解后的还原糖得率提高了,当PHCT相对摩尔含量(以葡萄糖环计)为16.67%时,纤维素水解成还原糖得率最大为23.54%;通过分析广角X射线衍射图发现,PHCT改性使微晶纤维素的结晶结构发生变化,无定形区增加,结晶指数下降,晶粒尺寸减小。     

新型阳离子羟乙基纤维素醚的合成

以羟乙基纤维素为原料、2-氯-4,6-二（N,N-二甲基-N-苄基-1,3-丙二胺）-1,3,5-均三嗪（BT）为改性剂,合成新型季铵盐阳离子羟乙基纤维素醚,讨论了影响产物取代度的主要因素。结果表明：在异丙醇稀释剂中,NaOH和改性剂的物料量比为1．2：1,改性剂和羟乙基纤维素的物料量比为1．5：1,反应温度为95℃、反应时间为5h时,产物的取代度最高达0．24。     

PREPARATION OF ZINC OXIDE NANOPARTICLE VIA UNIFORM PRECIPITATION METHOD AND ITS SURFACE MODIFICATION BY METHACRYLOXYPROPYLTRIMETHOXYSILANE

Zinc oxide nanoparticles were prepared by uniform precipitation using urea hydrolysis. The ZnO precursor was slowly deposited from aqueous solution. Anionic surfactant was added into solution to block ZnO crystal growth and its agglomeration. Then ZnO nanoparticles were synthesized by the calcination of the precursor at high temperature. Transmission electron microscope (TEM) observation and particle size analyzer demonstrated that the ZnO nanoparticle exhibited nearly spheric shape with 10–40 nm particle size. The surface of the ZnO nanoparticle was modified by methacryloxypropyltrimethoxysilane (MPS). FT-IR (Fourier transform-infrared spectrophotometry) and XPS (X-ray photoelectron spectrophotometry) revealed that MPS was grafted onto the zinc oxide nanoparticle. XRD (X-ray diffraction) showed that the ZnO nanoparticle was a hexagonal crystal with a perfect crystalline structure, and its crystalline morphology was not altered through surface modification. The activation index (AI) of the modified ZnO nanoparticle was measured. It was found that the surface of the ZnO nanoparticle was changed from hydrophilicity into hydrophobicity via surface modification, implying the enhancement of its compatibility with organic polymers. FE-SEM (field scanning electron microscopy) showed that the modified ZnO nanoparticles were homogeneously dispersed in PVC matrices. Consequently, ZnO nanoparticles were integrated with PVC matrices by the grafting organic molecule.     

超声辅助合成阳离子醚化剂2,4-二(二甲氨基)-6-氯-[1,3,5]-三嗪

用三聚氯氰和二甲胺为原料,借助超声辅助合成了一种阳离子醚化剂2,4-二(二甲氨基)-6-氯-[1,3,5]-三嗪(BDAT)。考察了超声辐射时间、反应温度、pH、投料比和超声功率对产物产率的影响。结果表明,超声辅助可以使固-液非均相反应在水溶液中顺利进行,在最佳合成条件下目标产物产率可达94%。通过核磁共振波谱、质谱、红外光谱对产物结构进行了确证。     

1,5-二乙酰基-2,4-二氧六氢-1,3,5-三嗪糖苷的合成及抗病毒活性

在氢氧化钠作用下,1,5-乙酰基-2,4-二氧六氢-1,3,5-三嗪与乙酰溴代糖反应,合成了标题化合物,系统的研究了反应条件对产率的影响,由元素分析、IR和1HNMR确认了所合成糖苷的结构。糖苷的最佳合成条件为:n(乙酰溴代糖)∶n(1,5-乙酰基-2,4-二氧六氢-1,3,5-三嗪)=1∶1,30°C下在丙酮中反应5 h。生测结果表明所合成的化合物具有较好的抗烟草花叶病毒(TMV)的活性。     

紫外线吸收剂中间体2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪的合成

以对氯苯甲醚、三聚氯氰为原料,通过格氏反应、Friedel-Craft反应来制备紫外线吸收剂中间体2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪,含量97.5%,总收率70.6%。该工艺成本低,条件温和,操作简单,适合工业化生产。     

羧基化改性纤维素凝胶球的制备和表征

以微晶纤维素为原料,利用NaOH/尿素体系对微晶纤维素进行溶解,得到再生纤维素溶液。采用滴定悬浮的方法制备纤维素水凝胶球,采用2,2,6,6-四甲基哌啶-1-氧基自由基（TEMPO）/NaBr/NaClO选择性氧化体系对纤维素水凝胶球进行氧化处理,获得羧基化改性纤维素水凝胶球,冷冻干燥得到羧基化改性纤维素气凝胶球。研究结果表明：羧基化改性纤维素水凝胶球的含水量为95.64%,吸附4h,亚甲基蓝的吸附量达到6.97mg/g。对羧基化改性纤维素气凝胶球进行傅里叶变换红外光谱（FT-IR）和扫描电子显微镜（SEM）表征分析,在1600cm^-1处出现了CO的伸缩振动峰,TEMPO的选择性氧化对样品起到羧基化改性作用,羧基化改性纤维素气凝胶增加了球形气凝胶的表面通透性,内部仍呈现网络结构,羧基化改性纤维素气凝胶球的密度为0.038g/cm³。     

Radiation degradation of microcrystalline cellulose in solid status

Pulverization and degradation are important pretreatment procedures in producing bio‐ethanol from cellulose. In this study, microcrystalline cellulose (MCC), a pure α‐cellulose, was degraded by γ‐irradiation. The average degree of polymerization, content of reducing sugar, crystalline structure, and molecular structure were investigated to elucidate the radiation effect on the degradation of MCC. The results manifested that γ‐ray destroyed part of the chemical bond and hydrogen bond, leading to the degradation of cellulose and increasing of the reducing sugar content. According to the Fourier transform infrared result, radiation degradation led to the formation of reductive carbonyl group. Meanwhile, radiation had slight influence on the crystalline structures of MCC. Therefore, the radiation degradation procedure is expected to benefit the further proceedings such as ultrafine treatment and enzyme hydrolysis of cellulose. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

PREPARATION OF ZINC OXIDE NANOPARTICLE VIA UNIFORM PRECIPITATION METHOD AND ITS SURFACE MODIFICATION BY METHACRYLOXYPROPYLTRIMETHOXYSILANE

Zinc oxide nanoparticles were prepared by uniform precipitation using urea hydrolysis. The ZnO precursor was slowly deposited from aqueous solution. Anionic surfactant was added into solution to block ZnO crystal growth and its agglomeration. Then ZnO nanoparticles were synthesized by the calcination of the precursor at high temperature. Transmission electron microscope (TEM) observation and particle size analyzer demonstrated that the ZnO nanoparticle exhibited nearly spheric shape with 10-40 nm particle size. The surface of the ZnO nanoparticle was modified by methacryloxypropyltrimethoxysilane (MPS). FT-IR (Fourier transform-infrared spectrophotometry) and XPS (X-ray photoelectron spectrophotometry) revealed that MPS was grafted onto the zinc oxide nanoparticle. XRD (X-ray diffraction) showed that the ZnO nanoparticle was a hexagonal crystal with a perfect crystalline structure, and its crystalline morphology was not altered through surface modification. The activation index (AI) of the modified ZnO nanoparticle was measured. It was found that the surface of the ZnO nanoparticle was changed from hydrophilicity into hydrophobicity via surface modification, implying the enhancement of its compatibility with organic polymers. FE-SEM (field scanning electron microscopy) showed that the modified ZnO nanoparticles were homogeneously dispersed in PVC matrices. Consequently, ZnO nanoparticles were integrated with PVC matrices by the grafting organic molecule.     

工业纯铁表面联苯胺电化学修饰膜的缓蚀作用

研究了联苯胺在工业纯铁表面的电化学修饰,对修饰工艺条件进行了探索,并采用多种电化学方法研究了修饰膜在不同介质中的耐蚀性能,用现代物理表面分析技术对修饰膜的组成和结构进行了研究.研究结果表明,联苯胺修饰膜对工业纯铁有很好的保护作用,在弱酸性、氯化钠以及强碱性介质中有良好的阻蚀性能.根据实验结果,本文对修饰膜的缓蚀机理进行了探讨.     

2,4-二(3-磺酸基苯胺基)-1,3,5-三嗪-6-淀粉醚的合成及粘度特性

以6-氯-2,4-二(3-磺酸苯胺基)-1,3,5-三嗪(BSTS)为醚化剂,二甲基亚砜(DMSO)为溶剂,合成了新型的含磺酸基团的淀粉衍生物2,4-二(3-磺酸苯胺基)-1,3,5-三嗪-6-淀粉醚(BSTSS)。考察了该醚化剂与淀粉反应的影响因素,得出了最佳制备条件为:n(BSTS)∶n(AGU)=0.4∶1,n(NaOH)∶n(AGU)=0.6∶1,反应时间4 h。通过IR、1HNMR表征了产品结构;通过GPC测量了产品的相对分子质量。研究了pH对溶液黏度的影响,结果表明,该淀粉醚溶液具有较好的抗酸碱性。     

三嗪型紫外线吸收剂的合成及性能

用格氏试剂偶联法合成了4个有代表性的三嗪型紫外线吸收剂:2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪、2,4-双(2,4-二羟基苯基)-6-苯基-1,3,5-三嗪、2-(2,4-二羟基苯基)-4,6-二苯基-1,3,5-三嗪和2,4,6-三(2,4-二羟基苯基)-1,3,5-三嗪,测定了它们的紫外光谱。其中,2,4-双(2,4-二羟基苯基)-6-(4-甲氧基苯基)-1,3,5-三嗪在UVB和UVA都有较强吸收,εmax=36000L/(mol.cm)(λmax=313nm),εmax=36333L/(mol.cm)(λmax=344nm),是其中最好的紫外线吸收剂。     

阳离子羟乙基纤维素溶液黏度性能的研究

以羟乙基纤维素（HEC）为原料,2-氯-4,6-二（N,N-二甲基-N-苄基1,3-丙二胺）1,3,5-均三嗪为改性剂,制备出不同取代度阳离子羟乙基纤维素。同时探讨了取代度及其浓度、阳离子及其浓度、转子转速、温度、pH值对阳离子羟乙基纤维素（CHEC）的黏性行为的影响。结果表明,阳离子羟乙基纤维素溶液黏度随着CHEC浓度增大、温度的升高、pH值的增加而减小。同一CHEC质量浓度下,取代度越高,转子的转速降低,黏度增大。CHEC在K₂SO₄溶液中的黏度总低于MgSO₄溶液中黏度;随着阳离子浓度的增加,CHEC溶液的黏度降低。     

2,4-二(4-联苯基）-6- (2-羟基-4-烷氧基苯基)-1,3,5-均三嗪紫外线吸收剂的合成与性能

以三聚氯氰为原料,通过格氏反应、Friedel-Craft反应合成了2-氯-4,6-二(4-联苯基)-1,3,5-均三嗪(Ⅳ);化合物Ⅳ在碱性条件下与溴代烷反应合成了3种2,4-二(4-联苯基)-6-(2-羟基-4-烷氧基苯基)-1,3,5-均三嗪(Ⅴ1～3)。用FTIR、MS、1HNMR对化合物Ⅴ1～3结构进行了确证,用TGA、UV-Vis对化合物Ⅴ1～3的热稳定性、紫外吸收及光稳定性进行了测定。结果表明,与市售商品化紫外线吸收剂UV-1577相比,化合物Ⅴ1～3的T5(质量损失5%时的温度)提高了40～60℃;具有更宽的吸收范围和更高的最大摩尔吸收系数(εmax)。化合物Ⅴ1～3的εmax分别为:79 448.28 L/(mol.cm)(λmax=318.5 nm),80 873.51 L/(mol.cm)(λmax=319 nm),76 774.7 L/(mol.cm)(λmax=319 nm)。     

Influence of dichloro-s-triazinyl reactive dyes on the fibrillation propensity of lyocell fibres

Four dichloro- s -triazinyl dyes and 2,4-dichloro-6- p -sulphoanilino-1,3,5-triazine have been applied by exhaustion methods to dried lyocell fibres. The method of application, of both dyes and agent, influenced the cross-linking performance and, in turn, the wet abrasion resistance of the treated fibre. However, dyeing alone, with any of the MX dyes used in this study, was insufficient to protect the fibre from wet abrasion problems during laundering. A comparison between one of the MX dyes, Chloranyl Orange MX-2R, and 2,4-dichloro-6- p -sulphoanilino-1,3,5-triazine on a mol-for-mol fixed basis, showed 2,4-dichloro-6- p -sulphoanilino-1,3,5-triazine to be greatly superior at protecting lyocell against wet abrasion.     

Isolation and Characterization of Microcrystalline Cellulose from Bamboo Pulp Through Extremely Low Acid Hydrolysis

Microcrystalline cellulose (MCC) has a wide range of applications in food, chemical, pharmaceutical industries, etc. In this study, the one-step preparation of MCC from bleached Kraft bamboo pulp (BKBP) by extremely low acid (ELA; acid concentration ≤0.1?wt %) was demonstrated. The experimental data indicate that the crystallinity, degree of polymerization (DP), and yield of MCC were strongly affected by the time and temperature of hydrolysis, as well as the concentration of hydrochloric acid (HCl). Rod-like MCC was obtained with a yield of 76.4% (based on the mass of original BKBP) and exhibited high crystallinity and narrow particle diameter distribution (78.7%, 30–70?μm) under optimal conditions (acid concentration of 0.08?wt%, 165?°C, 40?min). The Fourier transform-infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurements showed that the resulted MCC maintained cellulose I structure. Thermal analysis demonstrated that the as-prepared MCC exhibited good thermal stability. The ELA hydrolysis process may provide a green alternative for the manufacture of MCC from bleached Kraft bamboo pulp.     

Preparation and characterization of poly(vinyl alcohol) nanocomposites made from cellulose nanofibers

A method using a combination of ball milling, acid hydrolysis, and ultrasound was developed to obtain a high yield of cellulose nanofibers from flax fibers and microcrystalline cellulose (MCC). Poly(vinyl alcohol) (PVA) nanocomposites were prepared with these additives by a solution‐casting technique. The cellulose nanofibers and nanocomposite films that were produced were characterized with Fourier transform infrared spectrometry, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. Nanofibers derived from MCC were on average approximately 8 nm in diameter and 111 nm in length. The diameter of the cellulose nanofibers produced from flax fibers was approximately 9 nm, and the length was 141 nm. A significant enhancement of the thermal and mechanical properties was achieved with a small addition of cellulose nanofibers to the polymer matrix. Interestingly, the flax nanofibers had the same reinforcing effects as MCC nanofibers in the matrix. Dynamic mechanical analysis results indicated that the use of cellulose nanofibers (acid hydrolysis) induced a mechanical percolation phenomenon leading to outstanding and unusual mechanical properties through the formation of a rigid filler network in the PVA matrix. X‐ray diffraction showed that there was no significant change in the crystallinity of the PVA matrix with the incorporation of cellulose nanofibers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

新型含三嗪结构氧杂膦菲阻燃剂的合成

以三聚氯氰、对羟基苯甲醛和9,10-二氢-9-氧杂-10-膦菲-10-氧化物(DOPO)为主要原料,经两步反应合成了一种新型含三嗪结构氧杂膦菲阻燃剂PN-FR。第一步反应以三聚氯氰、对羟基苯甲醛为原料,二氯甲烷和水为混合溶剂,相转移催化剂作用下回流反应2 h,得2,4,6-三(4-醛基苯氧基)-1,3,5-三嗪(ZJT),收率98.8%;第二步在n(DOPO)∶n(ZJT)∶n(催化剂)=3.2∶1∶0.8,66℃回流反应3 h条件下得目标产物PN-FR,收率95.8%。用FTIR、EA、1HNMR、LC/MS、TG和DSC对中间体和产物作了结构表征和热性能分析。将该阻燃剂初步应用于环氧树脂绝缘层压板的阻燃,当阻燃剂质量分数为15%时,绝缘层压板氧指数达到36.2,通过UL-94 V-0级测试。该文研究工作的新颖性,已为四川省科学技术信息研究所2006年10月26日出具的第A0601512号《科技查新报告》所证实。     

主链型液晶聚氨酯的合成及性能研究

以4,4′–二羟基联苯与6–氯–1–己醇为原料,合成一种具有液晶性的中间体4,4′–双(6–羟己氧基)联苯(BHHBP),再分别与1,6–己二异氰酸酯、甲苯–2,4–二异氰酸酯、异氟尔酮二异氰酸酯、4,4′–二苯基甲烷二异氰酸酯、苯二甲基二异氰酸酯反应合成了五种结构不同的主链型液晶聚氨酯(PUR)。用核磁共振波谱仪、傅立叶变换红外光谱仪、热重分析仪、差示扫描量热分析仪、偏光显微镜和X射线衍射仪等表征了中间体BHHBP以及所合成的PUR的结构与性能,并详细探讨了PUR的结构对材料热性能和液晶性能的影响。     

蒙脱土结构和性质对催化不饱和脂肪酸二聚化反应的影响

钠基蒙脱土经过一次插层有机改性和二次插层有机改性后制得有机改性蒙脱土,作为催化剂用于催化不饱和脂肪酸二聚化反应制备二聚酸。采用XRD、SEM、TEM、FTIR和TG等检测手段对有机改性后蒙脱土的内层结构和性质进行分析。实验表明改性后蒙脱土层间距由1.48 nm扩大到3.82 nm,而且保持原来的夹心结构不变。蒙脱土的表面形貌和内部结构发生改变,表面变得疏松,内部层间距扩大且插层剂含量增加,分散实验表明二次插层有机改性蒙脱土在不饱和脂肪酸中分散性能优异。相同条件下,二次插层有机改性蒙脱土催化不饱和脂肪酸二聚化反应,二聚酸产率75.33%,是未改性蒙脱土催化制得二聚酸产率的2.14倍,并通过FTIR、¹H NMR和LC-MS证实合成的产物为二聚酸。