含氟乳液与环氧乳液成膜过程与自分层的探讨

综述了乳液成膜过程,结合含氟乳液与环氧乳液的共混乳液,介绍了共混乳液自分层的预测理论.利用乳液成膜模型和自分层的预测理论探讨了影响自分层共混乳液成膜的因素,研究表明:两种共混树脂的玻璃化温度(Tg)相差小于8℃;树脂的乳胶粒径在200nm左右;共混乳液形成连续的乳胶膜后再在高于最低成膜温度(MFT)的40℃下退火一段时间,可以形成具有底面合一结构;两种树脂分别呈现出优异的表面性能和附着性能的乳胶膜.     

含氟乳液与环氧乳液成膜过程与自分层的探讨

综述了乳液成膜过程，结合含氟乳液与环氧乳液的共混乳液，介绍了共混乳液自分层的预测理论。利用乳液成膜模型和自分层的预测理论探讨了影响自分层共混乳液成膜的因素，研究表明：两种共混树脂的玻璃化温度（Tg）相差小于8℃；树脂的乳胶粒径在200nm左右；共混乳液形成连续的乳胶膜后再在高于最低成膜温度（MFT）的40℃下退火一段时间，可以形成具有底面合一结构；两种树脂分别呈现出优异的表面性能和附着性能的乳胶膜。     

含氟无规两亲聚合物存在下含氟无皂乳液制备及表面性能研究

以含氟无规两亲聚合物(ASRF)为稳定剂,甲基丙烯酸六氟丁酯(FA)、苯乙烯等为单体,制备出含氟丙烯酸酯共聚物无皂乳液(PFAE)。研究了ASRF、FA用量对PFAE稳定性、乳胶膜吸水率和表面自由能的影响,并讨论了热处理对乳胶膜性能的影响。结果表明:适当增加ASRF和FA用量、提高处理温度,均有利于降低乳胶膜的吸水率和表面自由能;处理温度从30℃提高至110℃,吸水率可从31.49%降至12.08%,乳胶膜表面自由能下降幅度接近13.6%。ASRF和FA对PFAE稳定性均有一定影响。     

共混与共聚对含氟整理剂防水性能的影响比较

通过细乳液聚合分别合成了丙烯酸十八酯(StA)非氟均聚物乳液及丙烯酸十八酯与甲基丙烯酸全氟己基乙酯(C6FMA)含氟共聚物乳液。通过喷淋测试发现,在相同含氟量条件下,经StA均聚物和StA/C6FMA共聚物共混乳液处理的面料防水性能优于含氟共聚物乳液。XPS分析表明,经共混乳液处理的面料表面含氟量明显高于含氟共聚物乳液,说明共混体系有利于含氟组分向表面离析。粒径测试显示,非氟均聚物粒径是含氟共聚物粒径的1.5～2.0倍。DSC分析发现,StA均聚物可以结晶。乳液粒径越大和结晶都有利于低表面能含氟组分离析到表面。通过这种途径可以降低防水整理剂的含氟单体用量,进而降低处理成本。     

有机硅型杂化乳液的制备及其在棉织物防水整理中的应用

为解决目前的含氟防水整理剂大多含有PFOA或PFOS类持久性污染物的问题,设计制备了一种环保型无氟有机硅织物整理剂。将KH-570改性后的SiO_2纳米粒子与有机硅大分子单体、甲基丙烯酸甲酯、丙烯酸丁酯等通过细乳液聚合,制备不同SiO_2含量的有机硅型杂化乳液。采用动态光散射(DLS)、视频接触角张力仪(CAM)和台式扫描电子显微镜(SEM)研究乳液的粒径、乳胶膜的表面能、棉织物整理后的疏水性能。结果表明:通过细乳液聚合的方法,可成功得到乳胶粒粒径为120～130 nm、稳定的有机硅杂化乳液,且乳胶膜的表面能可达21.34～21.80 mN/m,棉织物整理后具有良好的防水性能和耐水洗性能。     

细乳液聚合制备含氟丙烯酸酯三元共聚物及性能表征

本工作以十二烷基硫酸钠（SDS）和脂肪醇聚氧乙烯醚（AEO-9）为乳化剂,采用细乳液聚合的方法,制备了甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）和全氟烷基丙烯酸酯（FA）三元共聚物。采用Fr—IR、^1H—NMR对聚合物的结构进行了表征;采用接触角法研究聚合物乳胶膜的表面性能。系统考察了超声均质强度（超声功率）、超声时间、FA用量、乳化剂用量等因素对细乳液聚合稳定性和乳液粒径及其分布的影响,优化的较佳细乳化工艺为：超声功率300W、超声时间3min、乳化剂用量为2．5％,FA单体质量分数〉4％;所制备的聚合物乳胶膜在低含氟量下即表现出优异的疏水疏油性能。     

丙烯酸酯聚合物表面施胶剂的合成与应用

采用种子半连续法乳液聚合工艺,以十六烷基三甲基氯化铵(CTAC)和壬酚基聚氧乙烯醚(OP-10)复配作为乳化剂,选用甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)和丙烯酸-β-异辛酯(2-EHA)为单体,经偶氮二异丁基脒盐酸盐(AIBA)引发上述单体的自由基乳液共聚反应,以制备一种阳离子型丙烯酸酯聚合物表面施胶剂。采用傅里叶红外光谱(FT-IR)和示差扫描量热分析仪(DSC)对聚合物进行表征;以马尔文粒度仪和透射电子显微镜(TEM)研究聚合反应中各种因素对乳液聚合的稳定性、聚合物乳胶粒子的粒径及其分布、乳胶粒子的形态结构的影响;通过扫描电子显微镜(SEM)、表面张力仪和Cobb值测定仪对采用该乳液表面施胶前后纸张的表面形貌、静态接触角以及抗水性进行观察和测试。研究结果表明,当AIBA用量为单体总量的1.6%、DMC用量为单体总量的5.0%以及2-EHA用量为单体总量的15.0%时,自制聚合物乳液的表面施胶效果最佳。     

含氟丙烯酸酯聚合物乳液研究现状与应用

综述了含氟丙烯酸酯聚合物与疏水疏油作用相应的结构特点和改性机理,分析了含氟丙烯酸酯的合成技术及应用现状。研究结果表明:乳液聚合法是目前该类材料的主要合成方法,在使用较低含量氟单体的情况下达到聚合物较好的表面性能,制备性能优异、价格低廉、符合环保要求的水性含氟丙烯酸酯共聚物乳液,并扩大其应用市场成为目前研究的重点。     

含氟有机硅细乳液的合成及性能

采用分步细乳液聚合法,合成了含氟有机硅细乳液。通过八甲基环四硅氧烷（D4）、四甲基四乙烯环四硅氧烷（Dv4）的阳离子开环聚合,先合成带乙烯基的有机硅聚合物,再自由基接枝含氟丙烯酸酯侧链。使用FTIR对聚合物的结构进行了表征,研究了Dv4单体和含氟丙烯酸酯单体（DFMA）的含量对乳液粒子的结构和乳液性能的影响。     

有机硅改性丙烯酸酯聚合物的方法

介绍了有机硅改性丙烯酸酯聚合物的两种方法:物理改性法(有机硅作为助剂与丙烯酸乳液共混、有机硅聚合物乳液与丙烯酸酯聚合物乳液共混)和化学改性法[缩聚法、加成聚合法(自由基共聚加成、硅氢加成)、核壳乳液聚合、乳液互穿聚合物网络(IPN)法];重点阐述了化学改性方法;展望了有机硅改性丙烯酸酯聚合物的发展趋势.     

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.     

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.     

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.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the