油墨溶剂在食品软包装中的残留及迁移规律

目的研究油墨溶剂在食品软包装材料中的残留及迁移行为,为食品包装生产企业提供安全风险控制方面的参考。方法采用顶空气相色谱-质谱联用(HS-GC-MS)技术,对印刷油墨的挥发性溶剂在食品软包装中的残留进行定性定量分析,以检出率较高的苯类溶剂甲苯、酯类溶剂乙酸丁酯和酮类溶剂丁酮为迁移研究对象,分别以PE,PP,PET/CPP,PET/PE,OPP/CPP,PET/PA/CPP为包装材料,研究油墨溶剂在水性食品模拟液(蒸馏水)、酸性食品模拟液(体积分数为3%的乙酸)、醇性食品模拟液(体积分数为10%的乙醇)和脂肪性模拟液(正己烷)中的迁移残留行为。结果研究表明,印刷后的食品软包装材料中大部分都有苯类、酯类和酮类等有机挥发物的残留,残留溶剂在食品模拟液中迁移量的大小依次为正己烷乙醇(体积分数为10%)乙酸(体积分数为3%)蒸馏水,而且对于不同的包装材料迁移量的大小也不同。结论油墨溶剂在食品软包装材料上的残留和迁移行为,主要与环境温度、食品性质以及包装材料的性能有关。     

固相萃取-气相色谱质谱联用法同时测定食品接触产品中邻苯基苯酚、噻苯咪唑、联苯及抑霉唑的迁移量

建立了气相色谱质谱联用技术同时测定邻苯基苯酚(OPP)、噻苯咪唑(TBZ)、联苯(DP)及抑霉唑(IMZ)迁移量的方法。样品分别采用水、4%乙酸、20%乙醇、50%乙醇作为食品模拟物,在特定条件下浸泡提取。浸泡液运用固相萃取技术净化提纯后过0.45μm微孔薄膜,在微极性柱上进行分离,质谱检测,外标法定量分析。优化条件下,OPP、TBZ、DP、IMZ在2-800μg/L浓度范围内与其峰面积线性良好,定量限分别为3、5、2和5μg/L(S/N=10)。在3个浓度水平进行添加实验,OPP、TBZ、DP、IMZ的平均回收率在70.4-112%之间,重复性精密度在1.78-6.72%(n=6)之间。结果表明,本方法操作简单快速、重现性好、准确度高。     

烟标环保印刷中溶剂残留的测定分析

目的 通过对水性油墨的印刷工艺进行条件优化,对比、分析不同工艺下的印刷品中溶剂残留的重复性和稳定性。方法 在相同的生产工序和生产批号下,从不同的生产车号中随机抽取平行样,采用顶空-气相色谱/质谱联用仪进行溶剂残留的测定。结果 乙醇和乙酸正丙酯的绝对偏差大于0.1 mg/m2,但其相对偏差小于10%,其他成分的绝对偏差均小于0.1 mg/m2,重复性较好;在相同分类、不同车号下,4类残留控制物的测定总量均远低于指标值,稳定性较好。结论 水性油墨既能满足环保印刷的要求,又能避免出现溶剂残留超标问题。     

谈谈复合膜软包装的分切工序

在复合膜软包装生产的各个工序中,印刷、复合、制袋往往因技术性强、工艺复杂而受到重视,投入较大的人力和物力,而分切工序常常被忽视。其实分切是软包装生产中的一个重要环节,它是生产卷膜成品的最后一道工序,负责成品的控制,卷膜的质量状况直接影响用户使用。分切又是制袋的前一个工序,起着承上启下的作用,如果分切膜的质量不好,会影响到制袋的质量和损耗,甚至会出现因分切的错误而导致整单产品报废的情况。所以软包装企业非常有必要重视分切工序。     

溶剂型凹印油墨有机残留的检测与分析

目的检测分析溶剂型凹版油墨中的有机残留,为溶剂型凹印油墨风险监控提供依据。方法参照QB/T 2929—2008的基础上建立12种有机溶剂的标准曲线。以双向拉伸聚丙烯薄膜(BOPP)为基材,在不同墨层厚度和干燥时间的条件下,检测12种有机溶剂残留量,分析残留量与墨层厚度和干燥时间的关系。结果有机溶剂残留量随墨层厚度增大而增加,随干燥时间增长而减少,均具有一定的线性趋势,丙酮和乙酸丙酯的残留量变化最为明显。结论研究结果能为塑料包装印刷在墨层厚度、干燥时间控制上提供科学依据,为食品相关材料风险监控标准的制定和修正提供数据依据。     

食品包装用塑料复合膜袋中13种有机溶剂残留量的测定

建立了顶空-气相色谱法测定食品包装用塑料复合膜袋中丙酮、乙酸乙酯、甲醇、2-丁酮、异丙醇、乙醇、苯、乙酸正丙酯,甲苯、乙酸丁酯、对二甲苯、间二甲苯、邻二甲苯等13种溶剂残留量的方法。本方法采用DB-FFAP色谱柱分离,氢火焰离子化检测器检测,13种溶剂能完全分离,各物质线性范围为0.007~50.0mg/m2,相关系数均不小于0.9995。样品加标回收率83%～95%,最低检出限可达0.004mg/m2。该方法简单,重现性好,是对GB/T10004-2008《包装用塑料复合膜、袋干法复合、挤出复合》中用顶空-气相色谱法测定溶剂残留量的一个很好的补充。     

固相萃取-高效液相色谱法测定水产品中甲氧苄啶残留量

建立固相萃取-高效液相色谱法检测水产品中甲氧苄啶残留量的分析方法。试样用15 m L 5%乙酸水-甲醇(70∶30,ν∶ν)、1 m L乙酸铅(200 g/L)、7 m L三氯甲烷混合液提取,提取液经Pro Elut PXC固相萃取柱净化,高效液相色谱仪对水产品中甲氧苄啶残留量进行测定。在0.02~0.20 mg/L范围内甲氧苄啶的质量浓度与色谱峰面积呈良好的线性关系,相关系数为0.999 3,方法的检出限(S/N=3)为0.02 mg/L,平均回收率为83.4%~87.0%,相对标准偏差(RSD)为3.9%~4.9%。该方法适合水产品中甲氧苄啶残留量的日常监测。     

超声提取葵粕绿原酸研究

研究了超声强化提取葵粕绿原酸中主要参数-乙醇浓度、液料比、超声功率、超声辐照方式、超声提取时间以及超声提取次数等-对绿原酸萃取率的影响.通过在单因素实验基础上进行的三因素三水平的Box-Behnken实验,得到了优化的工艺条件:在乙醇浓度为70%、辐照方式占空比9s:6s、超声提取30min的条件下,液料比为27.3ml/g,超声功率为200W,提取3次,绿原酸的萃取率可达到98.87%.     

微波辅助萃取-超高效液相色谱/静电场轨道阱高分辨质谱法快速测定纺织品中有害有机溶剂残留量

建立了1个快速测定纺织品中有害有机溶剂残留量的超高效液相色谱/静电场轨道阱高分辨质谱(UPLC/Orbitrap HRMS)方法,该方法以乙醇为萃取溶剂,100℃下微波萃取纺织品中残留的有害有机溶剂,萃取液直接进行UPLC/Orbitrap HRMS,提取离子色谱峰面积外标法定量。对样品的提取条件、分析条件进行了优化。该方法的定量限为0.5μg/kg~10.0μg/kg。在3个不同加标浓度水平下,方法的平均加标回收率为81.8~94.5%,相对偏差偏差为3.8%~10.5%(n=9)。该方法简便快速,灵敏度高,定量限低,可有效地解决纺织品中残留的有害有机溶剂的快速测定问题。     

气相色谱—质谱联用测定皮革中N,N-二甲基甲酰胺含量

本文建立了以乙酸乙酯为萃取溶剂,通过超声提取,气相色谱-质谱联用技术对皮革中N,N-二甲基甲酰胺残留量进行定性和定量的分析方法。该方法的回收率为95.93～101.83,检出限为1.50μg/mL。该方法前处理简单、快捷,准确度好、精密度高,可以适用于皮革等产品中N,N-二甲基甲酰胺残留量的定性筛查和精确测定。     

Prepation and Stability of Aqueous-Based Enteric Polymer Dispersions

Aqueous, colloidal dispersions of the enteric polymers, cellulose acetate phthalate (CAP), hydroxypropyl methylcellulose phthalate (HP-551, and polyvinyl acetate phthalate (PVAP) have been developed; and their application in tablet film coating demonstrated. The formation of free phthalic acid as a result of phthalate ester hydrolysis was monitored during storage of the dispersions. Increased free phthalic acid concentrations were found to adversely affect physical stability in dispersions of the cellulose polymers. Storage temperature and pH effects on phthalate ester stability were also considered     

Prepation and Stability of Aqueous-Based Enteric Polymer Dispersions

Abstract

Aqueous, colloidal dispersions of the enteric polymers, cellulose acetate phthalate (CAP), hydroxypropyl methylcellulose phthalate (HP-551, and polyvinyl acetate phthalate (PVAP) have been developed; and their application in tablet film coating demonstrated. The formation of free phthalic acid as a result of phthalate ester hydrolysis was monitored during storage of the dispersions. Increased free phthalic acid concentrations were found to adversely affect physical stability in dispersions of the cellulose polymers. Storage temperature and pH effects on phthalate ester stability were also considered     

分散液液微萃取--气相色谱法测定海水中的邻苯二甲酸酯

本文以分散液液微萃取作为样品的前处理技术,建立了气相色谱-氢火焰离子化检测器分析海水中邻苯二甲酸酯的新方法。优化了分散液液微萃取的萃取条件,6种邻苯二甲酸酯线性范围在1.0-50.0μg/mL之间,R≥0.9953,回收率在92.5%~106.4%之间,最低检测限为0.15μg/mL。将方法应用于海水中邻苯二甲酸酯类的检测,易于操作,分析结果可靠。     

Determination of the Acidic Degradation Products, Acetic, Propionic, Butyric, and Phthalic Acid in Aqueous Pseudolatexes of Cellulosic Esters by High Performance Liquid Chromatography

An isocratic, reversed-phase HPLC method was developed to quantify the organic acids, acetic, propionic, butyric, and phthalic acid, formed as a result of ester hydrolysis, in pseudolatexes of cellulosic esters. Colloidal dispersions of cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate were prepared by a microfluidization-solvent evaporation method. Dispersions of cellulose acetate phthalate were prepared by redispersion of a spraydried commercial pseudolatex. The acids were detected at 210 nm, the mobile phase being 0.025 M phosphate buffer: methanol (80:20 v/v%, pH 3.0). The peak height response was linear over the studied concentration range of 2 - 10 mM/L for the aliphatic acids and 20-100 μM/L for phthalic acid. The minimum detectable quantities for acetic, propionic, butyric, and phthalic acid were 0.02 mM/L, 0.05 mM/L, 0.1 mM/L, and 0.0005 mM/L, corresponding to a % change in acetyl, propionyl, butyryl, and phthalyl content of 4.0 × 10⁴, 1.2 × 10³, 2.9 × 10³, and 2.8 × 10^-5 for a 30% w/v pseudolatex. The colloidal polymer particles were separated by ultracentrifugation, filtration, or flocculation with aluminum chloride solution before analysis of the aqueous phase. Similar acid concentrations were obtained for the three separation methods. The recovery from spiked samples was almost complete for acetic, approximately 90% for propionic acid, and less than 80% for butyric acid.     

Determination of stable carbon isotopic compositions of low molecular weight dicarboxylic acids and ketocarboxylic acids in atmospheric aerosol and snow samples

We report a new method developed for the determination of stable carbon isotopic composition of homologous alpha,omega-dicarboxylic acids and phthalic acid isolated from environmental samples such as atmospheric aerosols and snow. Dicarboxylic acids are derivatized with BF3/1-butanol to dibutyl esters, which are analyzed for the stable carbon isotopic composition using a capillary GC interfaced to on-line combustion isotope ratio mass spectrometer. The delta13C values for individual dicarboxylic acid are then calculated from delta13C of 1-butanol and butyl ester derivative using a mass balance equation. The accuracy of the delta13C measurement for C2-C10 diacids is within 0.8 per thousand. We report a few examples of the delta13C ratios of saturated C2-C9 alpha,omega-dicarboxylic acids, unsaturated (maleic, phthalic) diacids, and oxocarboxylic acids in the aerosol and snow samples.     

Determination of the Acidic Degradation Products,Acetic, Propionic,Butyric, and Phthalic Acid in Aqueous Pseudolatexes of Cellulosic Esters by High Performance Liquid Chromatography

Abstract

An isocratic, reversed-phase HPLC method was developed to quantify the organic acids, acetic, propionic, butyric, and phthalic acid, formed as a result of ester hydrolysis, in pseudolatexes of cellulosic esters. Colloidal dispersions of cellulose acetate, cellulose acetate butyrate, and cellulose acetate propionate were prepared by a microfluidization-solvent evaporation method. Dispersions of cellulose acetate phthalate were prepared by redispersion of a spraydried commercial pseudolatex. The acids were detected at 210 nm, the mobile phase being 0.025 M phosphate buffer: methanol (80:20 v/v%, pH 3.0). The peak height response was linear over the studied concentration range of 2 – 10 mM/L for the aliphatic acids and 20–100 μM/L for phthalic acid. The minimum detectable quantities for acetic, propionic, butyric, and phthalic acid were 0.02 mM/L, 0.05 mM/L, 0.1 mM/L, and 0.0005 mM/L, corresponding to a % change in acetyl, propionyl, butyryl, and phthalyl content of 4.0 × 10⁴, 1.2 × 10³, 2.9 × 10³, and 2.8 × 10^?5 for a 30% w/v pseudolatex. The colloidal polymer particles were separated by ultracentrifugation, filtration, or flocculation with aluminum chloride solution before analysis of the aqueous phase. Similar acid concentrations were obtained for the three separation methods. The recovery from spiked samples was almost complete for acetic, approximately 90% for propionic acid, and less than 80% for butyric acid.     

Polyethylene glycol compounds for functional hydraulic fluids

New compounds of phthalate; -phosphate, -borate, -phosphate-borate; polyethylene glycol and 2-(2-butoxy ethoxy ethanol) were synthesized, with the aim of producing new high performance functional hydraulic fluids. The synthesis process involves two stages: first, the synthesis of base compounds which are products of the reactions of phthalic acid anhydride, polyethylene glycol and acid [phosphoric, boric, phosphoric-boric and/or phthalic]. Then, the reaction of phthalic acid with 2-(2-butoxy ethoxy) ethanol. The base compounds so prepared, together with diluents and additives were formulated for the second stage of the synthesis process. The effectiveness of standard specification tests was investigated. Property improvement may be attained by the incorporation of phthalic acid anhydride in the reaction. Our new functional hydraulic fluids can be produced more economically and can monitor any pollution caused by fluid operations in the petroleum industry. Electronic Publication     

Synthesis and characterization of a potential material as internal fixation of bone fracture

A new unsaturated poly (ester–amide) viz phthalic anhydride–maleic anhydride–hexane diamine–ethylene glycol–neopentylene glycol copolymer was prepared by melt polycondensation and characterized after sealed end with benzyl alcohol. Mechanical properties and degradation behavior of the cross-linked unsaturated poly (ester–amide) were measured. Moreover, the hydrolysis behavior of cross-linked unsaturated poly (ester–amide) in 1.0 mol/L NaOH standard solution at room temperature was also studied. At the same time, preliminary biocompatibility under mice skin was evaluated. All the preliminary results suggested that the copolymer might be a potential bone internal fixation material.     

丙烯酸酯对水性聚氨酯乳液及其塑料凹版油墨的性能的影响

采用乳液共聚法制备了聚氨酯-聚丙烯酸酯(PUA)复合乳液,并以酞菁蓝为颜料配制了塑料凹版水性油墨,讨论了乙烯基单体甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)对PUA 乳液及其水性油墨的性能的影响.结果表明,随着MMA含量的增加,PUA复合乳液的粘度先减小然后增大.随着m(BA)/m(MMA)的增加,PUA乳液的粘度先变大随后减小.用固含量为30%(质量分数,后同)的PUA乳液配制的水性油墨的粘度随时间推移而增大.水性油墨的初干性随MMA与聚氨酯(PU)的质量比的增加而变好,但随着m(BA)/m(MMA)的增加而变差.当MMA与PU的质量比达到0.25后,水性油墨不仅对PET薄膜具有优异的附着牢度,对OPP薄膜也有良好的附着牢度,同时具有良好的耐水耐酸性能.