核壳型阳离子丙烯酸酯硬挺剂的制备

采用种子乳液聚合方法,制备了一种核壳型阳离子丙烯酸酯乳液.通过红外光谱(FT-IR)、透射电镜(TEM)和Zeta电位分析了自制乳液的结构和性能.应用对比试验表明:与市售硬挺剂相比,自制的核壳型阳离子丙烯酸酯硬挺剂拥有较好的硬挺效果,实际应用效果有所提高.     

核壳型阳离子聚丙烯酸酯硬挺剂的合成及应用

以丙烯酸酯类化合物为主要原料,采用种子乳液聚合法合成了核壳型(软核硬壳)阳离子型聚丙烯酸酯乳液.通过红外光谱仪(FT-IR),热重/差热综合热分析仪(DTA-TG)和Zeta电位仪分析了自制乳液的结构和性能,并测试了竹浆纤维织物经硬挺剂与氟系防水防油剂一浴法整理的效果.试验结果表明,该阳离子型聚丙烯酸酯乳液与氟系防水防油剂具有良好的相容性和稳定性,整理后织物可达到与二浴法整理相近的硬挺、防水与防油效果,且织物富有弹性.     

核壳型聚丙烯酸酯乳液硬挺整理剂的合成与应用研究

以苯乙烯（ST）、甲基丙烯酸甲酯（MMA）、丙烯酸丁酯（BA）为主要原料,采用乳液聚合法,合成了性能稳定的核壳型聚丙烯酸酯硬挺剂。通过红外光谱仪（FT—IR）验证了聚合物的分子结构。对涤纶织物进行硬挺整理,可有效满足实际要求的整理工艺为：硬挺剂600g／L,200℃焙烘1．5min。结果表明,合成的硬挺剂具有优良的硬挺效果,整理后的织物高温不泛黄或泛黄不明显,厚重感明显增加且耐水洗性良好。     

甜菜碱型聚丙烯酸酯硬挺剂的合成与应用

为提高聚丙烯酸酯硬挺剂的力学性能并改善其热软冷脆的缺点,以可聚型甜菜碱两性离子单体为功能单体,甲基丙烯酸甲酯为硬单体,丙烯酸丁酯为软单体,采用无皂乳液聚合法制备甜菜碱型聚丙烯酸酯硬挺剂,用于汽车安全带(高强力涤纶织物)的硬挺整理.测试了硬挺剂及其整理后织物的各项性能.结果表明:甜菜碱含量越高,硬挺剂乳胶颗粒的粒径越小、...     

环保型硬挺剂的合成及在纺织品上的应用

以丙烯酸和丙烯酸酯等为原料,氧化还原体系引发,经乳液聚合法合成了性能优良的环保型硬挺剂.通过红外光谱(FT-IR)、Zeta电位和扫描电镜(SEM)等表征了它的结构和性能.探讨了pH值、培烘温度等因素对纺织品硬挺整理后综合性能的影响,利用正交试验得出该硬挺剂对棉织物的优化整理工艺条件:硬挺剂用量100 g/L,整理液pH为5,170℃焙烘2 min.棉织物经该整理剂优化工艺整理后的硬挺度提高了80%以上,水洗5次后硬挺度下降10%左右,具有较好的耐洗性.     

聚丙烯酸酯硬挺整理剂的制备及应用

采用水相核-壳乳液聚合法,分别以甲基丙烯酸甲酯和丙烯酸丁酯为主要硬单体和软单体,以丙烯酸为功能单体,制备核壳型聚丙烯酸酯硬挺剂,通过对单体、乳化剂、引发剂、电解质等的选择或用量优化,以及聚合反应温度的控制,优化了聚丙烯酸酯硬挺整理剂的制备条件:甲基丙烯酸甲酯(MMA)∶丙烯酸丁酯(BA)∶苯乙烯(ST)∶丙烯酸(AA)=48∶27∶12∶3(质量比),乳化剂4%(对单体重,下同)、阴非离子乳化剂质量比3∶1,引发剂过硫酸铵0.4%,电解质碳酸氢钠0.4%,聚合反应温度85℃;在该条件下制备得到的硬挺剂乳液性能稳定。将其用于涤纶机织物硬挺整理,可使织物抗弯长度从1.8 cm提高至4.8 cm,且整理效果具有较好的耐洗性,织物白度和强力几乎不受影响。     

棉织物拒水拒油硬挺复合整理探讨

选取丙烯酸型及三聚氰胺型硬挺剂与含氟防水剂同浴整理棉织物,研究同浴整理对拒水拒油、硬挺整理效果及棉织物强力的影响.发现三聚氰胺型硬挺剂与含氟防水剂同浴整理对拒水拒油及硬挺效果影响不大;丙烯酸型硬挺剂与含氟防水剂同浴整理会严重影响拒水拒油效果,但此类硬挺剂硬挺效果好于三聚氰胺型,因此在对硬挺效果要求高的情况下,可采用两步法整理.     

氟代丙烯酸酯共聚物的合成及应用

采用不饱和的含氟单体与丙烯酸酯类单体在常压下反应合成核壳型含氟丙烯酸酯共聚物,并用其整理亚麻织物。采用傅里叶红外光谱仪、透射电子显微镜、X光电子能谱等分析手段研究了乳液及其胶膜的结构以及亚麻织物整理后应用性能的变化。结果表明:半连续种子乳液聚合法可合成出纳米级核壳结构的氟代丙烯酸酯共聚物乳液,用其整理亚麻织物,织物变得光滑平整。整理后的亚麻布样断裂强力明显提高,透湿透气性略有降低。胶膜对水和十六烷的接触角分别为98.32°和65.58°。     

核壳型丙烯酸酯乳液的涂料印花

采用自制的核壳型乙烯基硅氧烷预聚物(PVPS)改性丙烯酸酯乳液作为黏合剂,应用于涂料印花。探讨了黏合剂原料中的功能单体、交联单体、PVPS及棉布阳离子改性等对印花性能的影响。结果表明,黏合剂用量为20.0%时,纯棉织物的干湿摩擦牢度分别为4～5级和3级,硬挺度4.6～5.1 cm,无黏连性,不堵网,表面滑爽性好。这类涂料印花黏合剂应用于纯棉布印花比涤纶更合适,纯棉织物经阳离子改性后印花,湿摩擦牢度可提高到3～4级。     

无甲醛聚丙烯酸酯乳液硬挺剂的制备及性能

以丙烯酸酯、苯乙烯、双丙酮丙烯酰胺和丙烯酸为单体,采用种子乳液聚合法制备了无甲醛聚丙烯酸酯乳液硬挺剂。讨论了乳化剂用量、阴/非离子乳化剂复配比、硬单体种类、软硬单体比例和双丙酮丙烯酰胺用量对硬挺剂性能的影响。结果表明:当乳化剂用量为5%(对单体质量)、阴/非离子乳化剂复配质量比为1∶2,苯乙烯为硬单体之一,软硬单体质量比为1.0∶1.4,双丙酮丙烯酰胺用量为1.5%(对单体质量),引发剂用量为1%(对单体质量)时,制备的聚丙烯酸酯乳液稳定性良好;用于棉织物硬挺整理,可以使织物抗弯长度明显增加,且具有较好的耐洗性。     

环保型硬挺整理剂GW—308的研制及应用

采用数种硬性单体，经预乳化乳液聚合研制成不含非环保物质、性能优良的硬挺剂ＧＷ－３０８，并与国内外一些同类产品相比，ＧＷ－３０８具有一定的先进性和较高的推广应用价值。     

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