阳离子可聚合表面活性剂DMSB的合成与性质

以甲基丙烯酸二甲基胺乙酯(DM)和1-溴十八烷(SB)为原料,合成了可聚合阳离子表面活性剂--甲基丙烯酰氧乙基十八烷基二甲基溴化铵(DMSB),利用红外光谱、核磁共振、元素分析、高效液相色谱等方法对目标产物进行分析和表征,并对其表面活性进行了研究.然后以偶氮二异丁腈(AIBN)为引发剂,将该表面活性剂与苯乙烯(st)、丙烯酸丁酯(BA)共聚制得了阳离子无皂乳液,将其应用于纸浆的施胶过程,结果表明,该乳液具有良好的施胶增效作用.     

改性胶原蛋白乳液施胶性能的研究

用乙烯类单体对从皮革废弃物中提取的胶原蛋白进行接枝聚合得到改性胶原蛋白乳液,采用红外光谱、激光粒径分布仪分别对接枝物结构和粒径分布进行了测定,用热重分析(TG)对产物的热稳定性进行了表征。将改性胶原蛋白乳液分别与淀粉及苯丙乳液进行复配,对瓦楞原纸进行表面施胶,考察施胶后瓦楞原纸的强度性能和抗水性,并与某造纸厂生产线上的施胶瓦楞原纸(苯丙乳液与淀粉复配作施胶剂)进行对比。结果表明,乙烯类单体与胶原蛋白发生了接枝反应得到改性胶原蛋白乳液,其粒径分布较均匀,热稳定性好。与纸厂施胶纸样相比,改性胶原蛋白乳液单独施胶的纸张环压指数低,抗张指数高,60 s吸水值基本持平;改性胶原蛋白乳液和淀粉复配后与纸厂纸样在环压强度与吸水值上持平,抗张指数优于纸厂纸样。     

阳离子型HDI三聚体乳液表面施胶剂的制备及其应用

以N,N-二甲基甲酰胺(DMF)为溶剂,以苯乙烯(St)、丙烯酸丁酯(BA)、甲基丙烯酸二甲氨乙酯(DM)为原料合成阳离子乳化剂,制备得到六亚甲基二异氰酸酯(HDI)三聚体乳液。讨论了乳化剂质量分数对乳液粒径及稳定性能的影响,并采用红外光谱、动态光散射测试对其结构、性能进行了表征;分析了施胶液浓度对施胶效果的影响,并测试了纸张的抗张强度、吸水性等性能。结果表明,乳化剂质量分数为14%时,所制备的HDI三聚体乳液粒径小且稳定性能好;施胶液浓度为7%时,施胶纸张耐折度相较于未施胶原纸增加了1087.5%,纸张抗张强度和湿抗张强度最大可达到7.30 k N/m和3.69 k N/m,且纸张吸水性降低至15.6 g/m~2,比原纸低了83.6%。所制得的HDI三聚体乳液表面施胶剂可以显著的提高纸张的施胶效果和物理性能。     

抗紫外水性聚氨酯施胶剂的制备及应用

以自制2-羟基-4-正辛氧基二苯甲酮(UV-531)为水性聚氨酯抗紫外改性剂,合成了一系列具有紫外吸收特性的水性聚氨酯乳液(UVWPU)。采用核磁氢谱、红外光谱、动态光散射粒径分析、紫外光谱等对改性后的水性聚氨酯进行结构表征和性能测试。将UVWPU应用于纸张表面施胶,探讨了UVWPU对纸张表面施胶性能的影响。核磁氢谱、红外光谱分析表明UV-531已成功制备并引入到UVWPU分子链上;当UV-531用量为2.0%时,UVWPU平均粒径为54.89nm,紫外吸光度为0.48,与纯水性聚氨酯乳液相比提升了585.7%。当UV-531用量为1.0%时,纸张的抗张指数及耐折度最好,分别为50.7N·m/g和76次,相比于原纸分别提高67.9%和61次,白度损失降低9.16%。     

苯乙烯-丙烯酸酯表面施胶剂的制备及应用

采用苯乙烯和丙烯酸酯合成了一种新型的表面施胶剂。分别利用红外光谱、激光衍射粒度分析仪和颗粒电荷测定仪对其结构性能、粒径分布及表观电荷密度进行表征测定,并对其应用性能进行研究。结果表明,合成的表面施胶剂粒径细小、粒度分布均匀,体积平均粒径为107 nm,均一性为0.250 2,带正电荷,电荷密度为747μeq/g。采用此施胶剂对纸张进行表面施胶后,纸张施胶度提高,白度和裂断长亦有所提高;将其与氧化淀粉复配,可以改善氧化淀粉的表面施胶性能。     

阳离子可聚合表面活性剂DMMB的制备与应用

以甲基丙烯酸二甲胺乙酯(DM)和1-溴十四烷(MB)为原料,通过亲核取代反应合成了甲基丙烯酰氧乙基十四烷基二甲基溴化铵(DMMB).利用红外光谱、核磁共振氢谱进行了结构表征,临界胶束浓度(cmc)为1.0×10-2mol/L,γcmc=32.3 mN/m.以DMMB为可聚合乳化剂,甲基丙烯酸甲酯、丙烯酸丁酯及苯乙烯为单体,过硫酸铵为引发剂,通过半连续乳液聚合法制备阳离子粘合剂乳液,将其作为粘合剂对纯棉织物进行涂料染色,当粘合剂用量达到50 g/L时,各项牢度均达到3级以上.     

有机硅改性苯丙乳液的制备及在表面施胶中的应用

以顺丁烯二酸-乙酯撑基[三甲基氯化铵]-十八烷基聚氧乙烯(20)醚酯(R303)为乳化剂,芬顿试剂为引发剂,利用无皂乳液聚合法将乙烯基三乙氧基硅烷(VTES)、苯乙烯(ST)、丙烯酸丁酯(BA)、N-羟甲基丙烯酰胺(NMA)接枝在阳离子淀粉主链上,制得了一种有机硅改性阳离子苯丙乳液(POSSA),并将其应用到表面施胶剂中。利用傅里叶变换红外(FTIR)光谱仪、激光粒度分析仪和扫描电子显微镜(SEM)对乳液的主组分结构、粒径分布和施胶前后纸张表面的微观形貌进行了表征,并对乳液的聚合工艺条件进行了探讨。结果表明:产物具有预期的结构,VTES的加入增强了施胶效果;当过硫酸铵(APS)用量6%~7%,H2O2用量2.4%~2.7%,R303用量2%~2.5%,NMA用量2.5%,VTES用量1.2%时,乳液的聚合过程稳定且纸张的施胶效果最好。     

阳离子疏水缔合聚丙烯酰胺的合成及性能

以环氧氯丙烷、丙烯酰胺(AM)及N,N-二甲基十八烷基叔胺为原料,制备了二甲基十八烷基(2-羟基-3-丙烯酰胺丙基)氯化铵(DMOHAC)阳离子表面活性单体,利用红外光谱及核磁共振氢谱方法对其结构进行了表征,并将DMOHAC与AM通过胶束共聚反应制备了阳离子疏水缔合聚丙烯酰胺P(DMOHAC/AM),通过红外光谱对聚合物的结构进行了表征,并利用表观黏度法考察了DMOHAC用量、疏水嵌段长度及疏水碳链长度不同的表面活性剂对P(DMOHAC/AM)溶液缔合性能的影响.结果表明,P(DMOHAC/AM)聚合物与阴离子表面活性剂在疏水缔合、静电吸引及氢键三重作用下能显著提高聚合物溶液的缔合性能,且阴离子表面活性剂与P(DMOHAC/AM)聚合物之间的缔合作用随表面活性剂烷基碳链长度的增加而增强.     

Gemini型可降解阳离子表面活性剂制备与应用

摘要:以环氧氯丙烷、己二酸和十八烷基二甲基胺为反应原料制备Gemini型双酯类阳离子表面活性剂,并通过傅立叶变换红外光谱仪对其结构进行表征。将该表面活性剂应用到棉织物柔软整理中,探讨了其对棉织物的折皱回复角、断裂强力、白度、柔软度、耐磨性以及亲水性等指标的影响,并与传统的织物整理剂双十八烷基二甲基氯化铵(D 1821)进行比较。结果表明,Gemini型阳离子表面活性剂对棉织物的各项整理性能均与传统整理剂D 1821相近,且耐磨性和亲水性更好。     

Gemini型可降解阳离子表面活性剂制备与应用

以环氧氯丙烷、己二酸和十八烷基二甲基胺为反应原料制备Gemini型双酯类阳离子表面活性剂,并通过傅立叶变换红外光谱仪对其结构进行表征。将该表面活性剂应用到棉织物柔软整理中,探讨了其对棉织物的折皱回复角、断裂强力、白度、柔软度、耐磨性以及亲水性等指标的影响,并与传统的织物整理剂双十八烷基二甲基氯化铵(D 1821)进行比较。结果表明,Gemini型阳离子表面活性剂对棉织物的各项整理性能均与传统整理剂D 1821相近,且耐磨性和亲水性更好。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.