丙烯酸酯类无氟拒水剂的合成及应用

以甲基丙烯酸十八烷基酯(SMA)、丙烯酸乙酯(EA)、丙烯酸正丁酯(BA)、甲基丙烯酸甲酯(MMA)和丙烯酰胺(AAM)为单体,十六烷基三甲基溴化铵(CTAB)和吐温-20(Tween-20)为复合乳化剂,偶氮二异丁脒盐酸盐(AIBA)为引发剂,采用乳液聚合法制备无氟拒水剂乳液。通过试验得到最佳合成工艺为:复合乳化剂CTAB与Tween-20的质量比为2∶1,乳化剂质量分数为6%(对单体总质量),引发剂质量分数为0.6%(对单体总质量),单体质量分数为30%,反应温度为70℃,反应时间为3 h。该工艺制得的无氟拒水剂乳液性能优异,稳定性好。经该拒水剂整理的涤纶织物对水的接触角约可达135°。     

环保型聚丙烯酸酯乳液粘合剂的制备及性能研究

使用反应型阴、非离子表面活性剂A和B作为乳化剂,过硫酸钾(KPS)作为引发剂,以丙烯酸丁酯(BA)和丙烯酸异辛酯(2-EHA)作为软单体,甲基丙烯酸甲酯(MMA)作为硬单体,丙烯酸(AA)作为功能单体,丙烯酸羟乙酯(HEA)作为交联单体,制备出环保型聚丙烯酸酯乳液。讨论了阴/非离子乳化剂配比、乳化剂用量、引发剂用量、反应时间、丙烯酸用量等因素对乳液性能的影响。     

苯乙烯改性丙烯酸酯乳液性能的研究

采用种子乳液聚合的方法,制备了一种具有核壳结构的苯丙乳液。研究了种子乳液的量、软/硬单体配比、丙烯酸、乳化剂、引发剂等因素对乳液聚合反应、乳液稳定性及涂膜性能的影响。结果表明:当种子乳液的量在12%~14%之间时,种子乳液中单体配比以St∶MMA∶BA=8∶5∶7为宜;在用St-MMA-BA-AA进行四元共聚反应时,整个体系中软硬单体配比为St∶MMA/∶BA=32∶28∶50时,所得乳液性能较好;复合乳化剂组成在Oπ-10∶SDS=1~2∶1之间时反应较好;引发剂采用连续滴加,且用量在0.5%~0.6%之间时,聚合反应速率稳定,单体转化率高。     

Pickering乳液型聚丙烯酸酯硬挺整理剂的合成及应用

以纳米SiO2为稳定剂、甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、双丙酮丙烯酰胺(DAAM)为交联单体、丙烯酸(AA)为功能单体、过硫酸铵(APS)为引发剂,采用Pickering乳液聚合法制备了环保型无甲醛硬挺整理剂。探讨了无机纳米粒子用量、油水相质量比、软硬单体质量比、不同交联单体对乳液及整理织物综合性能的影响。结果表明,当纳米SiO2占单体总量4%、油水相质量比为2∶5、MMA与BA质量比为3∶2、DAAM、AA、APS占单体总量的1.7%时,乳液性能最优。将所制得的乳液用于纯棉织物硬挺整理,棉织物的硬挺度从4.4 cm增至11.1 cm,水洗5次后硬挺度仍有9.2 cm;棉织物断裂强力从320.0 N提升至365.5 N,且整理后织物具有一定的拒水性能。     

纯丙乳液型哑光水性上光油的合成与应用

本文以丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)和丙烯酸(AA)为共聚单体,十二烷基硫酸钠为乳化剂,采用过硫酸铵作为引发剂,采用常压连续聚合的方式,制备出水性上光油用的纯丙乳液树脂。结果表明,当乳化剂用量在4%,引发剂用量为0.7%,软硬单体比例为1.5∶1时,合成的乳液表观透明度高、黏度适中(20m Pa·s-100m Pa·s之间),粒径在80nm左右。当流平剂用量为3%时,光油的稳定性、流平性能、耐水、耐化学品性能及耐摩擦性能优良,涂膜干燥后光泽度可达47.9%。     

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.     

阴离子自交联苯丙乳液的成膜抗水性能研究

以苯乙烯(St)、甲基丙烯酸甲酯(MMA)为硬性单体,丙烯酸丁酯(BA)为软性单体,N-羟基甲基丙烯酸酰胺(N-MA)为自交联单体,以丙烯酸(AA)、α-甲基丙烯酸(MAA)作为功能单体,采用预乳化种子乳液聚合法合成了稳定的自交联苯丙乳液。考察了苯乙烯用量、乳化剂用量、自交联单体用量及功能单体用量对乳液涂膜吸水率的影响,结果发现,稳定自交联苯丙乳液的适宜合成条件为软硬单体质量比mBA∶(mSt+mMMA)为0.9～1.1,St用量在25%～27%,乳化剂用量为1.5%～2.5%,阴离子和非离子乳化剂配比为1∶1,N-MA用量为2.5%,AA和MAA用量均为0.5%,此条件下合成乳液的转化率达到95%以上,涂膜抗水性好,膜平滑、透明且无气泡,可见该自交联苯丙乳液有着较优异的稳定性、成膜性和涂膜抗水性。     

有机无机杂化改性丙烯酸上光乳液的制备

采用半连续种子乳液聚合方法,并结合预乳化工艺,选用乳化剂K-12与高效乳化剂OP-10进行复配,以St、BA分别为硬软单体,DAAM、ADH和AA为功能性单体,APS为引发剂,Na HCO3为缓冲剂。在核壳反应温度分别为75℃和90℃,转速200r/min的条件下,制备出了固含量为30%的具有核壳结构和良好上光效果的苯丙乳液。通过改变乳化剂用量、反应温度、功能性单体用量、交联剂用量、保温时间,探讨其对乳液转化率,稳定性及上光效果的影响,以得到最佳的反应条件,并制得具有较高转化率和稳定性的乳液,在用作表面上光剂时可明显提高纸张光泽度。     

皮革涂饰用聚丙烯酸酯纳米乳液的合成及性能研究

以丙烯酸丁酯(BA)、丙烯酸甲酯(MA)、丙烯酸(AA)和丙烯酸羟乙酯(HEA)为单体,以AEO9、十二烷基硫酸钠与正戊醇为乳化剂,制备了皮革涂饰用聚丙烯酸酯纳米乳液.研究了单体配比、乳化剂浓度、反应时间和反应温度等对反应的影响.所得纳米乳液的粒子直径为30nm,用FTIR、TEM、DSC、SEM等对聚丙烯酸酯纳米乳液的结构及性能进行了表征.聚丙烯酸酯纳米乳液用作皮革涂饰剂时,具有柔软、耐候性强、粘接性好、耐磨、致密紧实的特点.     

含氟自交联丙烯酸树脂皮革涂饰剂的制备与性能/

用丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)、丙烯酸羟丙酯(HPA)、甲基丙烯酸十二氟庚酯(DFMA)、双丙酮丙烯酰胺(DAAM)、甲基丙烯酸(MAA)为单体,经过混合单体的预乳化,用十二烷基硫酸钠(SDS)、AEO-9、16~18醇为乳化剂,在过硫酸铵(ASP)引发剂作用下通过乳液聚合法合成了一种含氟自交联型丙烯酸树脂乳液。探讨了不同单体配比对乳液及涂膜性能的影响。研究发现当主要单体配比为w(BA)∶w(MMA)∶w(DFMA)∶w(HPA)=46.6∶32.2∶6∶3、DAAM用量w(DAAM)=2.0%、MAA用量w(MAA)=1.0%1.3%时,乳液反应稳定,单体转化率最高,用于皮革涂饰时涂膜的拉伸强度、耐湿擦性能等优于常规丙烯酸树脂涂饰剂。     

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