新型含氟丙烯酸酯拒水剂的合成及应用北大核心

采用甲基丙烯酸十二氟庚酯(Actyflon-G04)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主要单体,脂肪醇聚氧乙烯醚(AEO-9)和十二烷基硫酸钠(SDS)为复配乳化剂,过硫酸铵(APS)为引发剂,通过半连续种子乳液聚合法,制备出新型含氟丙烯酸酯共聚物乳液.分析了该含氟丙烯酸酯拒水剂的最佳合成工艺,并应用到棉织物上.最佳合成工艺为:m(BA)∶m(MMA)=5∶3,Actyflon-G0430%(对单体总质量),乳化剂2.5%(对单体总质量),引发剂0.9%(对单体总质量),聚合反应温度80℃,保温时间3 h.将拒水剂处理到棉织物上,整理后织物对水的接触角可达125.0°,耐静水压为145.8 mm,具有良好的拒水效果,并且织物手感、透气性能变化不大.     

新型含氟丙烯酸酯拒水剂的合成及应用

采用甲基丙烯酸十二氟庚酯(Actyflon-G04)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主要单体,脂肪醇聚氧乙烯醚(AEO-9)和十二烷基硫酸钠(SDS)为复配乳化剂,过硫酸铵(APS)为引发剂,通过半连续种子乳液聚合法,制备出新型含氟丙烯酸酯共聚物乳液.分析了该含氟丙烯酸酯拒水剂的最佳合成工艺,并应用到棉织物上.最佳合成工艺为:m(BA)∶m(MMA)=5∶3,Actyflon-G0430%(对单体总质量),乳化剂2.5%(对单体总质量),引发剂0.9%(对单体总质量),聚合反应温度80℃,保温时间3 h.将拒水剂处理到棉织物上,整理后织物对水的接触角可达125.0°,耐静水压为145.8 mm,具有良好的拒水效果,并且织物手感、透气性能变化不大.     

含氟丙烯酸酯乳液织物整理剂

以甲基丙烯酸六氟丁酯(Actyflon-G02)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸(AA)为原料,采用半连续种子乳液聚合方法制备短链含氟丙烯酸酯乳液功能整理剂,并将其应用于纯棉织物整理上;用红外光谱、XPS、粒度测定等手段对乳液聚合物进行结构表征与分析。结果表明,制备乳液共聚物的单体转化率高达97.75%,凝胶率为0.56%,乳液聚合物固含量为32.5%,平均粒径为101.0 nm,胶膜吸水率为8.12%,乳液稳定性较好;棉织物经其整理后对水的接触角有明显提高。     

纳米ZnO/有机氟硅改性聚丙烯酸酯乳液的合成及应用

为提高棉织物的抗紫外线、疏水和柔软性等服用性能,以纳米ZnO、甲基丙烯酸十二氟庚酯、3-(异丁烯酰氧)丙基三甲氧基硅烷、甲基丙烯酸甲酯、丙烯酸丁酯为反应单体,采用半连续种子乳液聚合法制备得到核壳型纳米ZnO/氟硅改性聚丙烯酸酯乳液,然后用于棉织物整理。借助红外光谱仪、X光电子能谱仪和热重分析仪等对制备的乳液进行结构和性能分析,使用织物风格仪等测试了整理后棉织物的应用性能。结果表明:制备的复合乳液呈核壳结构,平均粒径为45.64 nm,Zeta电位平均值为-43.4 mV;整理后棉织物的紫外线透过率为2.13%,紫外线防护系数为50.18,具有良好的抗紫外线防护性能;整理棉织物的水接触角为136.14°,其弯曲刚度和动、静摩擦因数均明显下降,具有优异的柔软性及光滑的手感。     

聚丙烯酸酯蓝色乳液的制备及应用北大核心

用经内交联单体和外交联单体改性后的内外两层丙烯酸酯聚合物对酞菁蓝颜料粒子进行包覆处理,制得蓝色乳液,并将其用于棉织物的涂料染色。结果表明,当聚合反应温度60℃,颜料质量(平均粒径160 nm)占蓝色乳液总质量的5%,单体总质量与颜料质量之比为3∶1,氧化还原引发体系APS-NaHSO(质量比=1.2∶1)3为单体总质量的0.8%,内交联单体N,N-亚甲基双丙烯酰胺为单体总质量的0.5%,外交联单体甲基丙烯酸缩水甘油酯为单体总质量的2.0%时,所得蓝色乳液稳定性高。染色布样的各项色牢度较高,且手感柔软。     

纳米SiO2/含氟硅防水透湿整理剂的制备及其应用

为提高涤纶织物的防水透湿性能,采用半连续种子乳液聚合法,以丙烯酸酯类单体为聚合单体,以纳米SiO₂ 、甲基丙烯酸十二氟庚酯(G04)、乙烯基三甲氧基硅烷( A-171) 为功能单体,制备出纳米SiO₂/含氟硅改性聚丙烯酸酯乳液,并将其应用于涤纶织物的整理。对改性共聚乳液的化学结构进行表征,并测试了整理后织物的应用性能。结果表明:各单体均参与乳液聚合反应,且改性共聚乳液的热稳定性大大提高,乳胶粒子平均粒径为66 nm;在整理剂中加入质量分数为2%的交联剂后,整理织物的静水压和耐水洗性能都得到显著的改善,其接触角为138°,相比未整理织物的防水性能明显提高;整理后织物的透湿率也有所提高,且经向断裂强力由315.6 N增加到493.4 N。     

聚丙烯酸酯蓝色乳液的制备及应用

用经内交联单体和外交联单体改性后的内外两层丙烯酸酯聚合物对酞菁蓝颜料粒子进行包覆处理,制得蓝色乳液,并将其用于棉织物的涂料染色。结果表明,当聚合反应温度60℃,颜料质量(平均粒径160 nm)占蓝色乳液总质量的5%,单体总质量与颜料质量之比为3∶1,氧化还原引发体系APS-NaHSO(质量比=1.2∶1)3为单体总质量的0.8%,内交联单体N,N-亚甲基双丙烯酰胺为单体总质量的0.5%,外交联单体甲基丙烯酸缩水甘油酯为单体总质量的2.0%时,所得蓝色乳液稳定性高。染色布样的各项色牢度较高,且手感柔软。     

有机氟防水剂的合成与应用

以丙烯酸十二氟庚酯(G04),甲基丙烯酸甲酯(MMA),丙烯酸丁酯(BA)为主要单体,脂肪醇聚氧乙烯醚AEO-9和十二烷基苯磺酸钠(SDBS)为复配乳化剂,过硫酸铵(APS)为引发剂,制备含氟丙烯酸酯共聚物.探讨了n(BA)∶n(MMA)、引发剂的种类及用量、乳化剂种类及用量、反应温度、反应时间等因素对含氟丙烯酸酯共聚物性能的影响,并将自制的含氟丙烯酸酯聚合乳液对棉织物进行整理,结果表明:当n(BA)∶n(MMA)=3∶2,APS用量0.6%,乳化剂为m(SDBS)∶m(AEO-9)=3∶2,用量6%,温度为75℃,预乳液滴加时间为3.5h,后续反应时间为1 h时,所制备的含氟丙烯酸酯共聚物具有良好的防水透湿性能.     

含氟丙烯酸酯拒水剂的制备

以苯乙烯(SM)、丙烯酸异辛酯(2-EHA)与甲基丙烯酸十二氟庚酯(Actyflon-G04)为反应单体,采用半连续种子乳液聚合方式,制备了含氟丙烯酸酯拒水剂.分析了含氟丙烯酸酯拒水剂的最佳合成工艺,对制备的共聚物进行傅立叶转换红外光谱表征,并将其处理到棉织物上.最佳合成工艺为:m(SM)∶m(2-EHA)=3∶2,Actyflon-G04 50%(对单体总质量),乳化剂2.5%(对单体总质量),引发剂0.8%(对单体总质量),聚合反应温度为80℃,保温时间为1.5 h.将合成的共聚物处理到棉织物上,整理后织物对水的接触角可达136.5°,具有良好的拒水性能.     

有机氟硅改性聚丙烯酸酯乳液的制备及应用

以丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸为单体,乙烯基三甲氧基硅烷、甲基丙烯酸十二氟庚酯为功能单体,YH-10为乳化剂,过硫酸钾为引发剂,通过半连续种子乳液聚合法制备有机氟硅改性聚丙烯酸酯乳液,并将有机氟硅改性聚丙烯酸酯乳液应用于尼龙型涤纶织物的整理。FT-IR结果表明：有机氟和有机硅单体参与了聚合反应,成功合成了有机氟硅改性聚丙烯酸酯乳液;SEM结果表明：有机氟硅改性聚丙烯酸酯乳液整理后的尼龙型涤纶织物表面形成了一层均匀的薄膜;TG结果表明：有机硅和有机氟功能单体的加入提高了聚丙烯酸酯乳液薄膜的热稳定性;应用性能测试结果表明：有机氟硅改性聚丙烯酸酯乳液粒径分布均匀,整理后的尼龙型涤纶织物与整理前相比,断裂强力、白度以及透湿性变化不大,水接触角达到了158.35°,使尼龙型涤纶织物具有超疏水性能。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

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

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

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.