壬基酚改性苯并噁嗪树脂基体的研究

采用DSC和流变仪研究了酚醛树脂、单官能苯并噁嗪和壬基酚改性的对二氨基二苯甲烷型苯并噁嗪的固化反应活性和黏温特性。并对壬基酚改性苯并噁嗪树脂用于热熔预浸料基体树脂的热性能、力学性能、黏温特性进行了深入研究。壬基酚改性苯并噁嗪树脂(BOZ-NP)可改善树脂的黏温特性,有效地降低固化反应温度,并具有较高的初始反应温度。加入25%的壬基酚的M-BOZ经180℃固化后的固化度达95%以上,5%失重率在342℃。加入10%的AG-80后BOZ-NP树脂的Tg在156.4℃。壬基酚和环氧改性苯并噁嗪树脂具有良好的力学性能和适宜的黏温特性,可作为热熔法苯并噁嗪预浸料树脂基体。     

SW280玻璃布/苯并噁嗪热熔法预浸料的性能研究

本文采用热熔法制备SW280玻璃布/苯并噁嗪预浸料,并对苯并噁嗪树脂工艺性、热失重性能,及复合材料动态热机械性能、高温力学性能保持率、阻燃性能等进行工艺试验和性能评价.结果表明,苯并噁嗪树脂软化点在41～42℃,最低黏度点为1835mPa·s,满足热熔法预浸料的制备要求;氮气氛围下起始分解温度280℃左右,800℃时残碳率可达61.3％.SW280玻璃布/苯并噁嗪复合材料力学性能优异,界面粘接良好,玻璃化转变温度为200℃,其200℃高温下的压缩强度、弯曲强度、弯曲模量和层剪强度保持率分别为90.6％、59.4％、83.2％和62.7％.SW280玻璃布/苯并噁嗪复合材料阻燃性能优异,无焰和有焰模式下最大烟密度均为0,氧指数＞58％,燃烧等级为V-1.     

90℃固化环氧预浸料的研制与性能

开发了一种可以在90℃固化并适用于热熔法制备预浸料的环氧树脂体系。树脂体系在不同温度下的粘度表明树脂体系具有良好的流动性能,通过差示扫描量热仪(DSC)确定树脂体系的固化工艺为70℃/2 h+90℃/6h。通过研究辊面温度和压力对纤维浸透性的影响及树脂的性能,确定了制备预浸料的工艺参数。T700碳纤维预浸料具有良好的工艺性能,其弯曲强度达1 408 MPa,剪切强度达73 MPa。     

聚芳醚酮增韧混合环氧树脂体系研究——Ⅱ.粘度、固化度随温度变化关系及材料性能

本文阐述了AG—80/E—44/PEK—C/DDS体系在不同温度下的粘度、固化度随时间的变化规律,并与其它热熔预浸料用树脂进行了对比,并使用旋转粘度计和DSC研究其粘度和固化度,用INSTRON拉力机和TMA测定了在不同温度下固化树脂及复合材料的力学性能,用SEM研究了试样断裂面及树脂和纤维的粘结形貌。建立了本体系在不同温度下粘度与时间关系的数学方程,证明该体系适于作为热熔预浸料所需用的树脂体系。由该树脂体系的热熔预浸料制备的复合材料,其性能与T—300/5208体系近似,SEM观察结果发现树脂和纤维的粘结情况良好。     

热熔预浸料用中温固化环氧树脂体系的制备

通过加入促进助剂丙烯酰胺制备一种新型热熔预浸料用环氧树脂体系.通过树脂体系的凝胶时间-温度曲线、粘度-温度曲线、DSC法确定了树脂的固化工艺,研究了复合材料的力学性能.结果表明,加入适量丙烯酰胺,可使体系粘度降低,使之与纤维有较好浸润性,其复合材料弯曲、剪切性能均优于未加入丙烯酰胺体系,对复合材料断面进行扫描电镜分析,纤维和树脂粘接良好.     

MA型苯并噁嗪/酚醛型氰酸酯共混体系的研究

以二苯甲烷二胺型苯并噁嗪和含醛基苯并噁嗪的混合物(MA)为基体树脂,通过加入具有高Tg的酚醛型氰酸酯(NCE)对其进行改性,对MA-NCE的凝胶化时间、固化行为及固化物热机械性能进行了研究;同时,引入二苯甲烷二异氰酸酯(MDI)作为阻聚剂,以期降低MA-NCE共混体系低温反应活性,并改善其加工性。实验结果表明,随着共混体系中NCE含量的增加,MA-NCE体系Tg提高而模量降低;MDI的加入则有效降低了共混体系反应活性,延长了凝胶化时间,使共混体系工艺性得到较大程度的改善。其中,MA-NCE-MDI 2-1-4%共混体系具有高的Tg和模量,以及良好的工艺性,可用于热熔法制备预浸料及高性能复合材料。     

环氧树脂基类玻璃高分子在苯并噁嗪树脂改性中的应用及回收

使用环氧树脂基类玻璃高分子（EPV）对苯并噁嗪树脂进行改性,可以在保证聚苯并噁嗪树脂加工性能、热性能、强度的情况下,有效地提高聚苯并噁嗪的韧性,同时,高价值EPV回收对于节能减排具有重要意义。将双酚A-苯胺型苯并噁嗪与EPV按照不同比例共混固化,制备具有良好力学性能、热性能的聚苯并噁嗪改性体系,并对其中的EPV进行回收。使用傅里叶变换红外光谱仪、差示扫描量热分析仪、扫描电子显微镜等研究了共混体系固化过程中的反应机理、固化物化学结构和聚集态结构,通过动态热机械分析仪、万能试验机、电子悬臂梁冲击试验机研究了共混体系固化物的热力学性能、弯曲性能、韧性。结果表明,EPV的添加提升了共混体系固化物的力学性能和热性能,当添加EPV质量分数达到15%时,共混体系固化物的冲击强度可达到16.6 kJ/m²,比纯聚苯并噁嗪提高69.4%;当添加EPV质量分数达到20%时,共混体系固化物的玻璃化转变温度、室温下的储能模量、弯曲强度相比于纯聚苯并噁嗪分别提高了17℃,11.6%,43.1%。依靠动态酯交换反应从共混体系固化物中回收得到与纯EPV结构一致的EPV。     

环氧树脂基类玻璃高分子在苯并噁嗪树脂改性中的应用及回收

使用环氧树脂基类玻璃高分子（EPV）对苯并噁嗪树脂进行改性,可以在保证聚苯并噁嗪树脂加工性能、热性能、强度的情况下,有效地提高聚苯并噁嗪的韧性,同时,高价值EPV回收对于节能减排具有重要意义。将双酚A-苯胺型苯并噁嗪与EPV按照不同比例共混固化,制备具有良好力学性能、热性能的聚苯并噁嗪改性体系,并对其中的EPV进行回收。使用傅里叶变换红外光谱仪、差示扫描量热分析仪、扫描电子显微镜等研究了共混体系固化过程中的反应机理、固化物化学结构和聚集态结构,通过动态热机械分析仪、万能试验机、电子悬臂梁冲击试验机研究了共混体系固化物的热力学性能、弯曲性能、韧性。结果表明,EPV的添加提升了共混体系固化物的力学性能和热性能,当添加EPV质量分数达到15%时,共混体系固化物的冲击强度可达到16.6 kJ/m²,比纯聚苯并噁嗪提高69.4%;当添加EPV质量分数达到20%时,共混体系固化物的玻璃化转变温度、室温下的储能模量、弯曲强度相比于纯聚苯并噁嗪分别提高了17℃,11.6%,43.1%。依靠动态酯交换反应从共混体系固化物中回收得到与纯EPV结构一致的EPV。     

高性能苯并噁嗪模压复合材料的研究

利用不同苯并噁嗪树脂体系胶液浸渍短切玻璃纤维,制得苯并噁嗪模塑料,并热压成型.通过对各树脂体系升温黏度变化、DSC固化行为以及凝胶化时间的研究,表明胺类催化剂或环氧-胺类催化剂的加入明显降低了苯并嗯嗪的热固化温度,提高了体系反应活性.对模压制品弯曲性能和耐热性能进行表征,得出加入环氧-胺类催化剂的苯并噁嗪体系,弯曲强度和弯曲模量分别达到565 MPa和22.7 GPa,明显高于普通酚醛、聚酯模压材料,玻璃化转变温度达到195℃,具有较好耐热性.模压制品的弯曲断面观察结果显示玻纤被树脂良好浸渍,纤维树脂间显示了良好的黏结性.     

一种用于新能源汽车电池密封盖的快速固化的环氧树脂基预浸料

将双酚A环氧树脂、阻燃型的环氧树脂和耐高温的多官能团环氧树脂在高温下熔融后搅拌均匀，选用具有潜伏性的中高温固化剂-促进剂的固化体系，两者混合后得到所需的树脂体系。通过环球法、差示扫描量热仪(DSC)和拔丝法实验方法确定了树脂糊的最佳配比，采用热熔法制备预浸料，研制出了一种能够快速固化的阻燃型耐高温环氧树脂基预浸料。采用树脂的DSC升温曲线和恒温曲线确定了材料的最佳固化温度和时间，测试了预浸料压制板材的力学性能、电性能和阻燃性能；另外，采用PCM模压工艺压制了新能源电池的密封盖制品，探究了最佳的模压工艺。结果表明，该材料的T_g有153℃,压制的材料阻燃要求能够达到UL 94 V-0级，且具有良好的力学性能和电性能。     

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。