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1.
以八甲基环四硅氧烷(D4)和甲基二乙氧基硅丙基二甲基十八烷基氯化铵(GS-18)为原料,AEO 7和AEO 9为乳化剂,十二烷基苯磺酸(DBSA)为催化剂,采用半连续乳液聚合法制备了阴离子 非离子复合型季铵盐改性聚硅氧烷(QAMP)微乳液。试验考察了催化剂DBSA含量、反应温度、预乳液滴加时间、非离子复合乳化剂(NCS)用量、D4含量和硅氧烷季铵盐含量对微乳液透光率的影响。结果表明,在一定范围内,微乳液的透光率随DBSA含量和非离子乳化剂用量的增加、反应温度的升高及预乳液滴加时间的延长而变大,随D4含量和硅氧烷季铵盐含量的增加而降低。当m(NCS)/m(D-4)和m(DBSA)/m(D4)都为0.3,聚合温度为75 ℃,预乳液的滴加时间为2 h时,可制备有机硅含量为20%,有机硅季铵盐含量1.5%(相对于D4的质量),透光率为92%的微乳液,其对涤纶布有较好的整理效果。  相似文献   

2.
毛用亲水性有机硅柔软剂的合成及应用   总被引:2,自引:0,他引:2  
用壬基酚聚氧乙烯醚(OP-10)作乳化剂,以十二烷基苯磺酸(DBSA)为催化剂,通过八甲基环四硅氧烷(D4)开环聚合,在一定条件下合成了阴离子有机硅微乳液.而后对其进行氨基、聚醚改性合成了毛用亲水性有机硅柔软剂.D4、OP-10、DBSA用量分别为微乳液质量的20%,4%~5%,3%~4%,60~70℃恒温反应5 h,预乳液滴加时间为1.5~2.0 h;改性剂用量为单体量的5%,聚醚、氨基改性剂质量比为1.5:1,反应温度为60~65℃,恒温反应2 h.合成的有机硅柔软剂为乳白半透明液体,略泛蓝光.结果表明,该产品不仅能使处理过的织物具有优良的柔软性和白度,并且还能赋予织物良好的亲水性.  相似文献   

3.
王晓萍 《中国油脂》2021,46(12):99-103
在无溶剂条件下利用酸性催化剂4-十二烷基苯磺酸(DBSA)催化β-谷甾醇与亚麻酸酯化合成β-谷甾醇亚麻酸酯,通过单因素试验和响应面法优化了酯化反应条件,并采用红外光谱对产物结构进行了表征。结果表明,最佳酯化反应条件为反应温度76 ℃,反应时间12 h,醇酸摩尔比1∶ 1.7,DBSA用量16%。在最佳条件下,β-谷甾醇转化率高达97.55%。红外光谱测试结果表明目标产物成功合成,实现了低温化学法合成β-谷甾醇亚麻酸酯。  相似文献   

4.
以八甲基环四硅氧烷(D4)与乙烯基三乙氧基硅氧烷(A-151)为单体,十二烷基硫酸钠(SDS)和脂肪醇聚氧乙烯醚(AEO9)为复合乳化剂,十二烷基苯磺酸作催化剂,制备了性能稳定的乙烯基改性聚硅氧烷乳液.讨论了乳化剂、催化剂、硅烷偶联剂用量,反应温度,反应时间等因素对聚合反应的影响.结果表明:当乳化剂用量4%(对单体总质量),催化剂用量8%(对D4质量),硅烷偶联剂用量5%(对D4质量),反应温度75℃,反应时间3h时,所得聚合物乳液的稳定性较好,单体转化率也比较高.  相似文献   

5.
以八甲基环四硅氧烷(D4)、端环氧双封头(F2D2)为原料,在四甲基氢氧化铵(TMAH)的催化作用下,合成了环氧双封端硅油.研究了反应物配比、反应温度、反应时间及催化剂用量对产品性能的影响,并用红外光谱对产物进行了结构表征.结果表明:当预先设定n(D4)∶n(F2D2)=20∶1时,最佳反应温度为110℃,反应时间为4.5 h,催化剂用量为0.045%,合成的环氧双封端硅油粘度为380m Pa·s,环氧值为0.019 0 mol/100 g,D4转化率为80.98%.并在最佳反应温度、反应时间、催化剂用量下,选取不同的反应物配比,合成出一系列不同分子质量的环氧双封端硅油,用以制备不同用途的三元共聚有机硅.  相似文献   

6.
用D72型阳离子交换树脂作为苯酐与甲醇反应合成邻苯二甲酸二甲酯的催化剂,研究了催化剂的用量、物料配比、反应温度、反应时间等因素对酯化反应的影响.结果表明:当催化剂的质量分数为4%,n(苯酐):n(甲醇):1:3,反应温度为110℃,反应时间为6h时,反应的酯化率可达99%。  相似文献   

7.
以十二烷基苯磺酸(Dodecyl benzenesulfonic acid,DBSA)+TX-100/环己烷/1-丁基-3-甲基咪唑四氟硼酸盐(Bmim BF_4)微乳体系为反应介质,Candida rugosa脂肪酶为催化剂,进行棕榈酸与乙醇酯化反应制备生物柴油,并考察离子液体用量、醇酸摩尔比、脂肪酶用量、反应温度、反应时间等因素对棕榈酸乙酯产率的影响。在单因素实验的基础上,根据中心组合Box-Benhnken实验设计原理,采用响应面分析法对生物柴油制备工艺进行优化。结果表明生物柴油制备的最佳工艺条件为:离子液体Bmim BF_4用量30%,醇酸摩尔比6.3∶1,脂肪酶用量为棕榈酸质量的14%,反应温度34℃时,反应时间3.0 h,此条件下,棕榈酸乙酯的产率为97.5%,该结果与模型预测值基本相符。  相似文献   

8.
以八甲基环四硅氧烷(D4)和1,3-二乙烯基-1,1,3,3-四甲基二硅氧烷(DVMS)为原料,三氟甲基磺酸为催化剂,通过阳离子开环聚合合成双端乙烯基聚硅氧烷(di Vi-PDMS),并以其改性聚丙烯酸酯,用于涂料印花。研究了催化剂用量、反应温度和反应时间对有机硅单体总转化率和合成产物di Vi-PDMS双键封端率的影响,并对di Vi-PDMS结构和相对分子质量进行表征,测定di Vi-PDMS改性聚丙烯酸酯胶膜及涂料的印花性能。结果表明:当催化剂用量0.15%,反应温度70℃,反应时间6 h,有机硅单体总转化率达91%;改变n(D4)∶n(DVMS),可合成出相对分子质量为2 000~20 000的di Vi-PDMS;di Vi-PDMS改性聚丙烯酸酯胶膜水接触角为98.50°,吸水率为7.39%,断裂延伸率、断裂强度分别为1 160%、2.65 MPa;其印花织物的耐干/湿摩擦色牢度达4级,手感柔软。  相似文献   

9.
吗啉型氨基硅油的合成工艺及应用研究   总被引:1,自引:0,他引:1  
采用酌-氯丙基甲基二甲氧基硅烷、吗啉、D4为原料,以四甲基氢氧化铵为催化剂,经过胺化、开环聚合反应制备了以吗啉为官能基团的硅油柔软剂,对影响反应因素进行了考察,确定了最佳工艺条件,并对其应用性能作了探讨.结果表明:在催化剂用量1×10-4~3×10-4(对单体质量)、反应温度110~160℃、反应时间6h条件下,得到含叔胺的吗啉型氨基硅油的氨值0.6mmol/g,白度86.1%.  相似文献   

10.
以八甲基环四硅氧烷(D4)与γ-甲基丙烯氧基丙基甲基二甲氧基硅烷(KH-571)为主要原料,采用乳液聚合法制得乙烯基聚硅氧烷低聚物乳液,将其应用于丙烯酸酯乳液的改性.优化了低聚物的聚合工艺,并进行了结构表征,结果表明:w(KH-571)=10%、w(催化剂DBSA)=10%、w(复合乳化剂)=3%,80℃下保温反应4~6 h,制备出稳定性较好、平均粒径50.0 nm且粒径分布较窄、最高转化率为89.4%的乳液.FT-IR表明得到乙烯基聚硅氧烷低聚物.用低聚物改性丙烯酸酯乳液,可得到平均粒径100.0 nm且分布较窄,乳液凝胶率低于4.0%,稳定性较好的硅丙乳液.  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

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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.  相似文献   

18.
<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  相似文献   

19.
《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.  相似文献   

20.
《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press  相似文献   

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