低温氩等离子体表面改性提高PET亲水性

为了提高PET材料表面的亲水性,应用低温氩等离子体对PET进行表面处理。对不同等离子体处理工作参数(放电功率、放电时间、工作气压)下PET薄膜表面的水接触角变化进行了规律性和原理分析。用IR和SEM分析了处理前后PET薄膜表面形态的变化。实验结果表明:不同等离子体处理工作参数下PET薄膜表面的水接触角的变化呈现不同的规律性;经等离子体处理后PET薄膜表面CO和CC键的数量增加,酯基数量减少,显著提高了薄膜的亲水性;但是低温氩等离子体处理后的PET薄膜放置一段时间后时效性问题比较明显。     

均匀介质阻挡放电用于材料表面改性的进展

在一定的条件下,大气压DBD能产生均匀、稳定的辉光放电,称为均匀DBD或大气压辉光放电(APGD).与丝状DBD相比,均匀DBD具有放电均匀、功率密度适中等优点,可以对材料表面进行更为均匀处理,因此具有更好的应用前景.在总结大量国内外文献的基础上,介绍了均匀介质阻挡放电(DBD)的产生结构和影响因素,综述了国内外均匀DBD材料表面改性的研究进展,并分析了改性中存在的主要问题及可能的解决办法.     

常压辉光放电引发聚乙烯纤维接枝丙烯酸

为提高聚乙烯(PE)纤维表面的亲水性,先在常压下用氦气辉光放电处理纤维,再接枝丙烯酸。对不同放电处理工作参数下PE纤维表面的接触角和接枝率变化进行规律性和原理分析。用IR和SEM、EDS分析处理前后PE纤维表面形态变化。实验结果表明:不同辉光放电处理工作参数下PE纤维表面接枝丙烯酸(AA)后使材料的接触角和接枝率呈现不同的规律性变化;经等离子体处理后接枝AA,在PE纤维表面成功引入了极性基团,显著提高了其亲水性。     

介质阻挡放电对水龙带增强层黏结性能的影响

针对水龙带增强层高强涤纶管状织物与三元乙丙橡胶内衬黏结性能差的问题,采用介质阻挡放电(DBD)等离子体对高强涤纶管状织物表面进行处理,研究了处理时间对纤维表面形貌和化学组成、丝束断裂强力、织物芯吸高度及剥离强度的影响。结果表明:经DBD等离子体处理后,高强涤纶表面产生明显的刻蚀痕迹,纤维表面极性官能团增加,织物芯吸高度增加,丝束断裂强力随处理时间的延长而下降;处理时间为60 s时,强度损失率为3.9%;处理后高强涤纶管状织物与三元乙丙橡胶内衬的黏结性能得到显著改善,处理时间为60 s时,剥离强度提升35.1%。     

等离子体引发丙烯酰胺接枝改性聚丙烯非织造布

采用常压等离子体设备,以空气为介质对聚丙烯(PP)熔喷非织造布进行处理,并在15%的丙烯酰胺水溶液中进行接枝聚合。表面衰减全反射红外光谱(ATR-FTIR)分析的结果表明,等离子体处理后,非织造布已接枝上聚丙烯酰胺(PAM)。经接枝改性的样品,亲水性得到持久提高,接触角由处理前的135°降低至110°,放置后接触角不变。未经接枝PAM的样品,放置后接触角回复至130°。扫描电镜观察的结果表明,等离子体处理对PP纤维产生明显的刻蚀,接枝后的PP纤维表面有突出物。     

常压等离子体处理羊毛织物的数码印花阳离子型反应性聚氨酯固色剂的合成及应用

为了改善羊毛织物的数码印花性能,采用介质阻挡放电(DBD)常压等离子体对羊毛织物进行表面改性。运用场发射扫描电镜(FESEM)、X射线光电子能谱仪(XPS)、视频光学接触角测量仪等表征手段,考察了等离子体处理对羊毛织物表观微形貌、化学组成、润湿性、白度、强力、手感及其数码印花性能的影响。研究结果表明:经常压等离子体处理后,羊毛纤维鳞片层被刻蚀和氧化降解;碳元素含量下降,氧元素含量显著增加,硫元素含量变化不大;织物白度无显著变化,润湿性能改善,断裂强力有所提高,使羊毛织物的印花性能明显改善。黑色和红色喷墨印花墨水在织物上的K/S值分别提高了77%和43%,且其干、湿摩擦牢度分别可达4级和3级以上,皂洗牢度可达4~5级,织物印花图案轮廓清晰,无明显渗化现象。     

常压等离子体处理羊毛织物的数码印花

为了改善羊毛织物的数码印花性能,采用介质阻挡放电(DBD)常压等离子体对羊毛织物进行表面改性.运用场发射扫描电镜(FESEM)、X射线光电子能谱仪(XPS)、视频光学接触角测量仪等表征手段,考察了等离子体处理对羊毛织物表观微形貌、化学组成、润湿性、白度、强力、手感及其数码印花性能的影响.研究结果表明:经常压等离子体处理后,羊毛纤维鳞片层被刻蚀和氧化降解;碳元素含量下降,氧元素含量显著增加,硫元素含量变化不大;织物白度无显著变化,润湿性能改善,断裂强力有所提高,使羊毛织物的印花性能明显改善.黑色和红色喷墨印花墨水在织物上的K/S值分别提高了77％和43％,且其干、湿摩擦牢度分别可达4级和3级以上,皂洗牢度可达4～5级,织物印花图案轮廓清晰,无明显渗化现象.     

汽车内饰材料拒水拒油整理及其性能表征

采用低温等离子体技术对再生聚酯纤维(PET)汽车内饰毯进行拒水、拒油处理。通过正交试验分析了全氟辛基磺酰胺单体质量分数、等离子体处理功率、等离子体处理真空度和等离子体处理时间4个因素的影响,并得出了最佳整理工艺条件。通过电子扫描电镜、红外光谱、接触角测量仪对采用最优工艺整理后的PET内饰毯进行性能测试和分析。结果表明:拒水拒油整理后纤维表面变得粗糙,全氟辛基磺酰胺单体有效地接枝到PET纤维表面。水、油液体在PET内饰毯上的扩散和渗透性明显变差,PET内饰毯获得了较好的拒水拒油效果。     

等离子体聚合改性在丙纶无纺布亲水整理中的应用

使用等离子体通过两步法对丙纶无纺布进行亲水整理。采用氮气等离子体处理丙纶无纺布,在纤维表面产生自由基;抽出氮气导入丙烯酸气体,利用自由基引发其聚合,并应用等离子体放电提高丙烯酸气体能量以加速聚合。采用红外吸收光谱(FTIR-ATR)、X射线光电子能谱(XPS)、扫描电镜(SEM)和接触角测试等方法对整理后静置3个月的丙纶织物进行测试。结果表明,整理后纤维在1 700～1 725 cm^-1处红外吸收略有增强,XPS发现整理后丙纶中存在羰基,说明丙烯酸对丙纶纤维实现了表面改性;整理对纤维形貌改变不大,仅表面出现少量鳞片状突起物;整理前丙纶无纺布的平均接触角为127°,整理后水滴于0.20 s内完全润湿,接触角为0°。     

氢氧化钠、氨水和冰醋酸对超高模量聚乙烯常压等离子处理效果的影响

超高模量聚乙烯分别浸于3%冰醋酸,3%氨水,10 g/L氢氧化钠24 h,然后阴干12 h后经常压等离子处理.用SEM和XPS对处理后聚乙烯进行表面形貌和元素含量表征,并测试纤维与树脂的层间剪切力和接触角.SEM结果表明:处理后各试样表面比未处理试样表面粗糙,氢氧化钠浸渍后的纤维表面有少许重结晶的氢氧化钠微粒.经XPS分析,处理后聚乙烯的氧元素含量比未处理的明显增加,纤维表面化学构成也发生了改变,极性基团大大增加.经等离子处理后层间剪切力比未处理的提高了6～7倍;接触角由未处理的99.4°下降到68°左右.经过各种不同试剂浸润的试样同直接处理的试样没有明显差别.     

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