醇解法分离废弃涤棉混纺织物工艺研究

采用乙二醇醇解法分离废弃涤棉混纺织物中的涤纶与棉纤维,研究了反应温度、反应时间、解聚催化剂醋酸锌用量、投料比等因素对醇解反应过程的影响,并对分离后的产物进行了表征。结果表明:醇解法可以有效地分离废弃涤棉混纺织物中的涤纶和棉纤维,醇解分离后的残留纱线为棉纤维;延长反应时间,升高反应温度,增加催化剂用量,降低投料比均有利于醇解分离;最佳醇解工艺条件为废弃涤棉织物10 g,乙二醇80 g,反应时间2 h,反应温度180℃,醋酸锌用量0.04 g,醇解率达95%。     

废旧涤棉混纺织物稀酸法分离工艺研究

以废旧涤棉军装为原料,采用稀酸法分离废旧涤棉混纺织物中的涤纶和棉纤维,考察了盐酸浓度、反应温度、反应时间等工艺条件对涤、棉的分离效果以及分离后涤纶、棉纤维的形貌及结构性能的影响。结果表明:当盐酸质量分数10%,反应温度90℃,反应时间90 min时,废旧涤棉军装中的涤纶与棉纤维分离效果最佳;经盐酸处理后,织物中剩下涤纶,棉纤维被去除,棉纤维小部分降解为还原性糖,大部分降解为棉渣粉末;盐酸处理后的涤纶化学结构、断裂强度、纤维形貌基本无变化,但初始模量显著下降;棉纤维经盐酸处理后形成的棉渣粉末仍为纤维素结构,但其结晶度有所提高。     

亚临界水条件下废旧涤棉混纺织物的分离

利用棉纤维和涤纶不同的耐酸性,结合亚临界水的特性,采用水热法对废旧涤棉混纺织物的分离回收进行了考察。以m(涤纶)∶m(棉)=1∶4的废旧涤棉织物为考察对象,HCl为催化剂,研究了水热温度、反应时间及HCl质量分数对分离过程的影响,并利用FTIR、XRD、SEM、HPLC及DSC对水热反应前后产物的物化性能进行了表征。结果表明:在水热温度150℃、反应时间3 h、w(HCl)=1.5%的水解条件下,混纺织物中棉纤维一部分水解形成固体纤维素粉末,产率约为48.21%;其余水解生成水溶性糖类物质,其中葡萄糖质量分数为15.57%;水热处理后的涤纶纱线回收率高达96.24%,断裂强度约降低3%。含有水溶性糖类的水解液可循环使用5次。     

乙二醇分离回收废弃涤棉混纺织物

利用乙二醇(EG)对废弃涤棉混纺织物醇解分离,并对醇解工艺优化,使涤棉易于分离,实现循环利用。通过单因素实验,考察了EG与织物的质量配比、醇解温度、醇解时间等因素对醇解分离效果的影响。研究表明:当EG与涤棉混纺织物的质量配比为3∶1、过滤温度60℃以上时最利于过滤回收,较适宜的醇解温度为196~210℃,醇解时间为2.5 h。回收后的棉纤维物理机械性几乎没有损伤,可被重复利用。同时,回收的再生PET特性黏度可达0.65 dL/g以上,可以满足纺丝要求。     

涤棉织物化学回收工艺研究

以废旧涤棉织物为原料,乙二醇(EG)为醇解剂,通过改变醇解时间、醇解温度、EG/废旧涤棉织物中聚对苯二甲酸乙二醇酯(PET)质量比(mEG/mPET)、催化剂种类及用量等研究了蓬松态下废旧涤棉织物的醇解工艺,以及醇解过程对涤棉织物中棉纤维性能的影响。结果表明:随着醇解时间、醇解温度的提高,mEG/mPET的增大,涤棉织物的醇解程度增大,各参数达到一定程度后醇解程度基本不变;最佳醇解工艺为涤棉织物中mEG/mPET为2/1,催化剂用量为涤棉织物中PET质量的0.30%,醇解温度196℃,醇解时间1 h;在乙酸锌、碳酸钠、乙酸钾、氯化镁4种催化剂中,碳酸钠综合催化效果最佳;经醇解过程后涤棉织物中棉纤维表面变得粗糙,力学性能有较大下降。     

涤纶织物化学镀镍前处理粗化工艺的研究

针对微波防护和电磁屏蔽用涤纶织物金属化的附着强度问题,研究了氢氧化钠、苯酚、聚乙二醇-600 3种粗化液对涤纶纤维的粗化效果。得出了较好的粗化液,并研究了该粗化液中氢氧化钠的质量浓度、粗化温度、粗化时间对织物纤维浸蚀效果的影响。结果表明,含90 g/L氢氧化钠的粗化液比另两种粗化效果更好,粗化温度80℃、粗化时间20 m in时,粗化效果最优,在涤纶基体上可获得良好结合力的化学镀层。     

石墨烯柔性导电涤纶织物的制备与性能

用乙二胺(EDA)和氢氧化钠对涤纶织物进行改性,得到氨基化改性涤纶。将改性涤纶浸渍氧化石墨烯(GO)溶液,涤纶表面的GO还原成还原氧化石墨烯(RGO)后得到具有导电性能的涤纶织物。采用SEM和Raman光谱对导电涤纶织物进行表征,并对其耐洗和耐摩擦性能进行了测试。结果表明,涤纶织物经150 mL EDA/L浴液和50 g/L氢氧化钠改性后对GO的吸附能力增强,织物导电性增加;改性涤纶的最佳导电整理工艺条件为:GO溶液质量浓度为2 g/L,pH=6,6 g/L保险粉在95℃还原60 min。在该条件下,织物上GO能够被较充分还原,改性涤纶的表面电阻值为14.575kΩ。SEM结果表明,未经改性的涤纶织物表面光滑,经导电整理后织物表面覆盖一层石墨烯薄膜;Raman光谱证实涤纶织物表面沉积了RGO,且织物上的GO被较充分还原。     

涤/棉混纺用新的丙二酸染料

前言由于这种染料可对涤/棉混纺织物同时进行理想的染色,并节省了机械费用、水、染料、化学品和能源的使用,因此这是一种理想的、引人注目的新染料。这项研究的宗旨是:确定合成的新染料能否具有同时染涤/棉混纺织物的涤纶和棉纤维的能力,并接近于相同的色泽。但对这种新开发的染料有两个主要问题需要解决。第一,这两种纤维之间的亲水性有着内在的差别。棉纤维吸水,一般可用水溶性染料染色。而涤纶纤维是疏水性的,在水中并不明显膨化,因此不能用水溶性染料染色。本文所提出的这种染料在碱性条件     

废旧涤棉面料组分溶解分离研究

采用离子液体[Amim]Cl对废旧涤棉混纺面料中含棉成分进行溶解回收。通过正交试验法,研究了温度、[Amim]Cl质量分数、时间、溶质与溶剂比例等因素对溶解过程的影响,得到优化的溶解工艺条件,同时研究了溶剂对涤纶的影响。结果表明:处理后的面料中接近99.2%的棉纤维被溶解,而涤纶没有明显损伤。影响棉纤维溶解效果因素的主次关系依次为:溶解温度,溶解时间,[Amim]Cl质量分数,溶质与溶剂质量比。优化的溶解工艺参数为:溶解温度95℃,溶解时间5 h,[Amim]Cl质量分数99%,溶质与溶剂质量比0.2∶3.5。红外分析表明:溶解处理的样品中棉的特征峰基本消失。     

纳米银/石墨烯负载涤纶织物的制备及其结构与性能研究

采用浸渍烘干法在经碱减量处理后的涤纶织物表面负载氧化石墨烯(GO),再通过纳米银(Ag)自组装制备具有良好电热性能的纳米Ag/石墨烯负载涤纶织物,研究了GO水分散液浸渍次数、柠檬酸钠溶液浓度及硝酸银溶液浓度对织物电热性能的影响,并对织物的结构、热性能及力学性能进行表征。结果表明：制备纳米Ag/石墨烯负载涤纶织物的较佳工艺条件为GO水分散液浸渍5次、柠檬酸钠溶液浓度0.1 mol/L、硝酸银溶液浓度0.1 mol/L;在纳米Ag/石墨烯负载涤纶织物制备过程中,GO和Ag⁺被还原成石墨烯和纳米Ag,并在织物表面形成致密且完整的高纯度纳米Ag;纳米Ag/石墨烯负载涤纶织物与未处理涤纶织物相比,具有更好的热稳定性,断裂强力相当;在3 V电压条件下通电60 s时,纳米Ag/石墨烯负载涤纶织物表面发热温度达到113℃,具有优异的电热性能。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。