可连续化生产的电刺激响应型液晶纤维制备及其性能

为解决电刺激响应液晶纤维在无外加电极下的柔性变色问题,提出一种同轴三明治结构的电致变色液晶纤维的制备方法.采用连续涂层法制备以导电纤维为内导电层,导电水凝胶为外透明导电层,聚合物分散液晶为电致变色层的电刺激响应液晶纤维.对导电纤维种类、聚合物分散液晶体系组分等对电刺激响应液晶纤维形貌和电致变色性能的影响规律进行分析.结...     

胆固醇液晶热致变色微胶囊的制备及其性能

为探索胆固醇类液晶在热致变色纺织品制备中的应用,采用三羟甲基三聚氰胺为壁材,胆固醇油醇碳酸酯和胆固醇壬酸酯的混合物为芯材,利用原位聚合法制备了胆固醇液晶微胶囊。对制备得到液晶微胶囊的微观形貌特征、热学性能以及热致变色性能进行了测试。测试结果表明：在乳化速度为6 000r/min、芯壁质量比为3：2、微胶囊包覆时反应溶液pH值为4.0的条件下,制备的液晶微胶囊粒径分布在10μm左右,微胶囊具有致密的壳结构、表面光滑的球形形态,以及良好的热致变色性能;它可在34.4 ～38.0 ℃的温度区间内,依次显示红黄绿蓝紫的颜色变化;其变色温度与人体体温接近,适合用于热致变色织物的制备。     

液晶高分子和聚丙烯的共混纤维(Ⅱ):纤维的牵伸性能

 在液晶高分子和聚丙烯的共混纤维中,液晶高分子以细而长的微纤维对聚丙烯起到强化作用。通过对初生纤维进行牵伸可以提高共混纤维中聚丙烯的取向度。故对牵伸过程中液晶微纤的受力状况以及影响牵伸后液晶微纤长度的各种因素进行了分析。     

超高效液相色谱法测定化妆品中对羟基苯乙酮含量

目的建立超高效液相色谱法(ultra performance liquid chromatography,UPLC)测定化妆品中对羟基苯乙酮含量的分析方法。方法样品前处理以甲醇为溶剂,超声30 min,采用色谱柱Atlantis~?d C_(18)分离,以甲醇-水(25:75,V:V)为流动相,流速为0.2 mL/min,检测波长为275 nm,经UPLC检测;同时对提取剂和提取时间、流动相比例、检测波长等条件进行优化。结果对羟基苯乙酮浓度在0.4376~21.83μg/m L范围内呈良好的线性关系,相关系数为0.9996,膏霜、乳、液等不同剂型样品回收率高,平均回收率分别为99.89%、99.83%和100.24%,RSD分别为0.75%、0.65%和0.46%。方法检出限为1.38μg/g。结论该方法简单、快速、准确,可适用于化妆品中对羟基苯乙酮含量的测定。     

Simultaneous determination of 21 preservatives in cosmetics by ultra performance liquid chromatography

An ultra performance liquid chromatography (UPLC) method has been developed for the simultaneous determination of 21 preservatives: 2-methyl-4-isothiazoline-3-ketone, bronopol, 5-chloro-2-methyl-4-isothiazoline-3-ketone, benzyl alcohol, 2-phenoxyethanol, methyl-p-hydroxy benzoate, ethyl-p-hydroxy benzoate, methyl benzoate, 4-hydroxybenzoic acid iso-propyl ester, propyl-p-hydroxy benzoate, 4-chloro-3-methylphenol, ethyl benzoate, 2-phenylphenol, 4-hydroxybenzoic acid iso-butyl ester, butyl-p-hydroxy benzoate, 4-chloro-3,5-dimethylphenol, phenyl benzoate, 2,4-dichloro-3,5-dimethylphenol, 2-benzyl-4-chlorophenol, triclocarban and triclosan in cosmetics. A Waters ACQUITY UPLC BEH C(18) column was used with 0.1% formic acid solution as the mobile phase under the condition of gradient elution. Preservatives were extracted with methanol by ultrasonicator, and then they were analysed by UPLC-PDA detector. All these preservatives were baseline separated in 8.5 min. The pre-treatment method of samples and the chromatographic condition of analysis were critically examined in this study. The recoveries ranged from 90.5 to 97.8%, with RSD values below 3.2%, and all correlation coefficients (r) were no less than 0.9997. Thus, this method could be used for analysing the preservatives in cosmetic products.     

基于染料掺杂型液晶微胶囊的电刺激响应智能纺织品的制备及其性能

针对电致变色液晶易流动,难以塑形而不易与纺织品结合应用的问题,在向列相液晶中掺杂二色性染料形成宾主材料,采用乳液聚合方法将其作为芯材封装在以聚甲基丙烯酸甲酯为壁材的微胶囊内,得到染料掺杂型液晶微胶囊。通过偏光显微镜分析液晶在限域条件下的独特光学性质,借助扫描电子显微镜、透射电子显微镜、热重分析仪等表征微胶囊的形貌结构及热学性能,并探讨微胶囊包覆对染料掺杂型液晶的驱动电压与使用寿命的影响。结果表明:制备的染料掺杂型液晶微胶囊具有明显的核壳结构,粒径为3 μm,芯材载量约为70%,驱动电压为3.6 V,远低于人体安全电压;以微胶囊为原料涂敷在导电织物上,其光学外观可在直流电源刺激下于无色态和有色态之间发生可逆转变,从而为优化电致变色液晶微胶囊器件制备工艺和提高纺织品柔性显示性能奠定基础。     

高效液相色谱串联质谱法测定水产品中的孔雀石绿和结晶紫

目的建立高效液相色谱串联质谱法检测水产品中孔雀石绿、隐色孔雀石绿、结晶紫、隐色结晶紫残留量的方法。方法待检水产品经乙腈提取,中性氧化铝固相萃取柱净化, 0.22μm微孔滤膜过滤后用高效液相色谱串联质谱进行检测。结果 4种化合物在0～100.0ng/mL浓度范围内线性关系良好,相关系数大于0.999,检出限均可达到0.25μg/kg,回收率为85%～110%,相对标准偏差均小于10%。结论本方法使用试剂少、步骤简单,适用于大批量水产品中孔雀石绿和结晶紫残留量的检测。     

化妆品中23种香料类致敏成分的高效液相色谱法测定

建立了同时测定化妆品中23种香料致敏成分的高效液相色谱法。样品经乙腈超声提取15min,以8000r/min离心5min,取上清液过滤后测定。采用Aglient ZORBAX SB-C18(4.6×250 mm,5μm)色谱柱, 以乙腈-水为流动相梯度洗脱,采用二极管阵列检测器多波长检测(200、210、240、290nm)。23种致敏成分的定量限分别为1.25、2.5、5.0、10.0μg/kg,线性范围内相关系数均大于0.99。在1倍定量限、2倍定量限,10倍定量限浓度的添加水平下平均回收率为80%-110%,相对标准偏差为0.5%-9.3%。该方法简单、准确、快速,适用于化妆品中23种致敏成分的测定。     

超高效液相色谱-串联质谱法检测鱼类中孔雀石绿、结晶紫及其代谢物

目的建立超高效液相色谱-串联质谱法测定鱼类中孔雀石绿、结晶紫及其代谢物的分析方法。方法本方法依据GB/T 19857-2005,样品用乙腈提取,分散固相萃取净化管净化后,采用色谱柱分离。样品经过离子化后进入质谱仪中,以水和乙腈为流动相,电喷雾正离子化模式(electrospray ionization,ESI+)和多反应检测(multiple reaction monitoring,MRM)扫描模式进行测定,同位素内标法定量。结果孔雀石绿和结晶紫及其代谢产物在0.2～2.0 ng/mL浓度范围内,线性关系良好(r 0.999),检出限均为0.5μg/kg。在0.5～2.0μg/kg水平内,目标物质的平均加标回收率在99.71%～112.86%之间,相对标准偏差均不超过13%。对72份鱼类样品进行检测,隐性孔雀石绿的检出率为1.38%,其余均未检出。结论该方法定量准确、分析时间短,适用于鱼肉中孔雀石绿和结晶紫及其代谢物残留量的定量检测。     

胆甾相液晶混合配比与服装热色效应的研究进展

介绍了胆甾相液晶的分子结构、光学性能、液晶性能及其在纺织方面的应用,重点综述了胆甾相液晶混合配比与其热色效应之间关系的研究进展,以期为国内液晶变色服装的研究同行提供一定参考。     

QuEChERS-超高效液相色谱-串联质谱法快速测定化妆品中糖皮质激素类药物

目的建立QuEChERS-超高效液相色谱-串联质谱法快速测定化妆品中16种糖皮质激素类药物的检测方法。方法样品经1%(V/V)甲酸-乙腈提取,加入氯化钠进行盐析,提取液经C₁₈50 mg、N-丙基乙二胺(primary secondary amine,PSA)100 mg、MgSO₄150 mg净化,采用Thermo Acclaim RSLC 120 C₁₈(2.1 mm×100 mm,2.2μm)进行分离,电喷雾正离子多反应监测扫描(multiple reaction monitoring,MRM)模式下进行测定,外标法定量。结果16种糖皮质激素在线性范围1~100 ng/mL内线性良好,相关系数r²在0.991~0.999之间,方法定量限为10μg/kg,16种糖皮质激素平均回收率在76.5%~109.3%之间,相对标准偏差为0.77%~2.41%。结论该方法操作简单、净化效果好、灵敏度、准确度和精密度均符合多残留检测技术要求,解决了化妆品中糖皮质激素类药物检测提取过程过于繁琐的问题,可为化妆品检测提供更方便、更快捷的检测方法支持。     

Influence of PEG-12 Dimethicone addition on stability and formation of emulsions containing liquid crystal

Oil/water emulsions, containing liquid crystals, were developed employing Andiroba oil, PEG-12 Dimethicone and Crodafos CES. It was evaluated the influence of silicone surfactants on the emulsions stability and on the formation of liquid crystalline phases and therefore, physicochemical characteristics, such as rheology and zeta potential, were evaluated. Emulsions were prepared by the emulsions phase inversion method. All the formulations presented lamellar liquid crystalline phases. The PEG-12 Dimethicone addition did not change microscopically the liquid crystalline phases. The emulsions containing silicone demonstrated lower viscosity than those without the additive. This is an important feature, as the silicone did not change the rheological profile; however, the addition of silicone still can be used as a viscosity controller. The formulations had their viscosity increased 15 and 150 days after their preparation. This characteristic shows that the emulsions have their organization increased along the storing time. In the analysis of zeta potential, we could verify that all formulations presented negative values between -39.7 and -70.0 mV. Within this range of values, the emulsion physical stability is high (Fig. 10). It was concluded that the addition of PEG-12 Dimethicone kept the liquid crystalline phase of the emulsion obtained with Crodafos CES, influencing in a positive way in the system stability.     

Simultaneous determination of some ultraviolet-absorbing chemicals in sunscreen cosmetics using a high-performance liquid chromatography method

A method of gradient elution high-performance liquid chromatography (HPLC) for simultaneous determination of 11 different ultraviolet-absorbing chemicals of phenylbenzlmldazole sulphonic acid, 4-aminobenzoic acid, benzophenone-4, benzophenone-3, isoamyl p-methoxycinnamate, 4-methylbenzylidene camphor, octocrylene, ethylhexyl methoxycinnamate, homosalate, ethylhexyl salicylate, methylene bis-benzotriazolyl tetramethylbutyl phenol was developed for the application to sunscreen cosmetic products. In this study, an Agilent SB-C18 analytical column (250 × 4.6 mm, 5 μm) was utilized and methanol, tetrahydrofuran and perchloric acid aqueous solution (0.2 mL HClO(4) + 300 mL H(2)O) were used for gradient elution at a total flow rate of 1.0 mL min(-1). The optimum conditions for 11 different ultraviolet-absorbing chemicals analyses were investigated. All calibration curves showed good linear regression with UV detection (311 nm) within test ranges. The correlation coefficients were better than 0.999 in all cases. The assay was simple, selective, convenient and reproducible and is suitable for the determination of ultraviolet-absorbing chemicals in commercial sunscreen cosmetic products. The use frequency of 11 different ultraviolet absorbents in 100 sunscreen cosmetics was investigated and statistically analysed. The ultraviolet absorbent of maximum use frequency was ethylhexyl methoxycinnamate.     

基于对羟基苯丙酸的生物基液晶共聚酯纤维的合成与性能

针对常规生物基纤维力学性能与耐热性不足的问题,以6-羟基-2-萘甲酸、对羟基苯甲酸和对羟基苯丙酸(HPPA)为原料,采用一锅熔融聚合法合成了生物基液晶共聚酯,并通过熔融纺丝制备得到初生纤维,对共聚酯及其初生纤维的结构与性能进行研究.结果表明:制备得到的生物基液晶共聚酯为向列型液晶,其熔点在200℃左右,并随着HPPA添...     

超高效液相色谱-串联质谱法测定化妆品中同分异构体构型糖皮质激素

目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定化妆品中同分异构体构型糖皮质激素(glucocorticoids, GCs)的分析方法。方法样品经饱和氯化钠分散、乙腈提取,亚铁氰化钾-醋酸锌沉淀大分子基质后,通过分散固相萃取技术(QuEChERS)净化。以0.1%甲酸水溶液和乙腈作为流动相迚行梯度洗脱,采用多反应监测模式(multiple reaction monitoring, MRM)对美白祛斑类化妆品中同分异构体构型糖皮质激素迚行定量和定性检测。结果 本方法完成了对糖皮质激素中最难以分离的差向同分异构体倍他米松、地塞米松以及它们的衍生物倍他米松醋酸酯、地塞米松醋酸酯的分离检测。在5.0、10和20μg/kg添加水平时的回收率为78.6%～102.7%,相对标准偏差小于10.60%(n=6),方法定量限为6.0μg/kg。结论 该方法快速、稳定、灵敏度高、选择性好,适合分析检测化妆品中非法添加的GCs类化合物。     

超高效液相色谱-串联质谱法同时检测水产品中 孔雀石绿、结晶紫及其代谢物的残留

目的建立同时检测水产品中孔雀石绿(malachite green,MG)、隐色孔雀石绿(leucomalachite green,LMG)、结晶紫(crystal violet,CV)和隐色结晶紫(leucocrystal violet,LCV)等残留量的超高效液相色谱-串联质谱(UPLC-MS/MS)的分析方法。方法样品经乙腈提取,经中性氧化铝柱净化,采用超高效液相色谱-串联质谱法以电喷雾正离子化模式(electrospray ionization,ESI+)和多反应监测(multiple reaction monitoring,MRM)扫描模式进行测定,以同位素内标法定量。同时考察了基质效应对检测结果的影响。结果水产品中MG、LMG、CV和LCV的基质效应不同,其中LCV的基质效应最为明显,加标回收率较低(约50%)。MG、LMG、CV和LCV 4种物质在0.2~5.0 ng/mL浓度范围内呈良好线性,相关系数均大于0.999,方法检出限为0.1~0.2μg/kg。MG、LMG和CV的加标回收率为93.5%~109.2%,相对标准偏差为5.4%~9.6%(n=6)。结论该方法仪器分析时间短、定量准确、检出限低,可用于检测水产品中MG、LMG、CV和LCV的残留量。     

Highly sensitive spectrometric method for determination of hydroquinone in skin lightening creams: application in cosmetics

A highly sensitive, simpler, faster and economical UV/visible spectrophotometric method has been established for the estimation of hydroquinone (HQ) in dilute organic matrices. The method is based on using ammonium meta‐vanadate as an oxidizing catalyst for conversion of HQ to p‐benzoquinone (BQ) in the presence of oxygen. As a result of higher absorption of UV light by BQ than by HQ, its signal has been utilized for determining HQ at the trace level. The effect of various parameters such as amount of oxidizing agent, stability time, temperature, acids and bases, solvents and interference by various compounds has been studied upon the absorption of BQ as HQ. Under optimized conditions, Beer’s Law was obeyed in the range of 0.025–2.00 μg ml^?1 HQ at 245.5 nm using 1 : 1 (V/V) 2‐propanol/water system with a lower detection limit of 7 ng ml^?1 and linear regression coefficient of 0.9998. Relative standard deviation of 1.5% was observed for 0.5 μg ml^?1 HQ solution (n = 11). The newly developed method has been successfully applied to diluted samples of various skin lightening creams for free HQ determination at the trace level. Comparison of the results obtained by the proposed method with those by a previously reported method proved its validity.     

N,N-二甲基乙酰胺/氯化钙体系对热致液晶聚芳酯纤维结构及性能的影响

为提高热致液晶聚芳酯(TLCP)纤维与基体材料的界面黏结性能,同时保持其优异的热学和力学性能,采用N,N-二甲基乙酰胺/氯化钙(DMAc/CaCl₂)体系对TLCP纤维进行表面改性制备TLCP/聚氨酯复合材料。借助单纤维万能测试仪、扫描电子显微镜、原子力显微镜、傅里叶红外光谱仪、X射线衍射仪、同步热分析仪和万能材料试验机等对改性前后的样品进行表征与分析。结果表明:TLCP纤维经DMAc/CaCl₂改性处理后表面条纹增多,平均粗糙度由96.42 nm增至438.60 nm;改性处理后的TLCP/聚氨酯复合材料的界面黏结性能有明显改善,平均剥离强度由0.71 N/mm提高到1.14 N/mm;改性后TLCP纤维分子结构无明显变化,纤维结晶结构不变,结晶度由69.00%降至64.45%;当DMAc体积分数不超过30%时,纤维的力学性能无明显下降。