笼形氨丙基聚倍半硅氧烷/聚乳酸杂化材料的制备与性能

用溶液共混的方法,制备了不同质量分数的笼形氨丙基聚倍半硅氧烷(OAPS)与聚乳酸(PLLA)杂化材料。用傅立叶红外光谱(FTIR)、差示扫描量热法(DSC)、动态热机械分析(DMA)、热失重分析(TGA)等手段对该体系进行了考察。结果表明,OAPS质量分数为5时,PLLA的羰基伸缩振动峰由1758cm-1红移至1748cm-1,OAPS氨基伸缩振动峰由3362cm-1红移至3296cm-1,说明PLLA羰基与OAPS氨基之间形成了氢键;随着OAPS质量分数由0增至5,OAPS/PLLA杂化材料的玻璃化转变温度(Tg)由47℃升高至56℃,熔融温度(Tm)由141℃升高至146℃,储能模量由1100MPa增至1250MPa;OAPS的加入没有改变PLLA的热分解温度。     

N,O-羧甲基壳聚糖的制备及表征

以壳聚糖为原料,成功地制备了水溶性良好的N,O-羧甲基壳聚糖,并采用傅立叶红外、X射线衍射、热失重分析、元素分析以及激光光散射等方法对所制备的产物进行了表征.红外谱图中在1 620 cm-1及1 429 cm-1处分别出现了-COO-的反对称及对称伸缩振动吸收峰,表明了羧甲基取代的发生.取代的结果极大地降低了产物的结晶度,表现为X-ray曲线中2θ=20°和2θ=10°与结晶有关的峰极大削弱.热失重的结果表明N,O-羧甲基壳聚糖中含有缔合水,故将此结论用于元素分析的结果处理中,可得到取代度为1.01.通过激光光散射Zimm作图法,得到产物的Mw=2.44×105.     

聚酰亚胺/二氧化硅纳米复合膜的电沉积与性能研究

本文首先采用低能乳化法制备聚酰胺酸盐(PAAS)纳米乳液,制备的PAAS纳米乳液的平均粒径为35.0nm,将PAAS纳米乳液与中性二氧化硅纳米溶胶按一定的比例混合后,分别在50、100和150V的电压下电沉积于电极上(沉积时间3min),电沉积复合膜经过热亚胺化得到聚酰亚胺/二氧化硅(PI/SiO2)纳米复合膜。FT-IR分析显示酰亚胺环上的C=O不对称伸缩振动特征吸收峰(1778 cm-1)和Si-O-Si的非对称伸缩振动和对称伸缩振动特征吸收峰(1116和802cm-1)。X射线能谱仪(EDS)测试结果表明电沉积膜中存在硅原子,而且随着二氧化硅投料量的增加硅元素的质量百分比相应提高。复合膜的SEM显示二氧化硅以纳米颗粒形式均匀分散在聚酰亚胺基体中。由TG测试得知,PI/SiO2纳米复合膜的热稳定性高于纯PI膜。     

笼形氨丙基聚倍半硅氧烷／聚乳酸杂化材料

郑州轻工业学院的张晓静等人采用溶液共混法制得系列不同质量分数的笼形氨丙基聚倍半硅氧烷（OAPS）与聚乳酸（PLLA）杂化材料。结果表明,OAPS质量分数为5％时,PLLA的羰基伸缩震动吸收峰由1758cm^-1红移至1748cm^-1,OAPS氨基伸缩震动吸收峰由3362cm^-1红移至3296cm^-1,说明PLLA羰基与OAPS氨基之间形成了氢键;     

热致液晶聚酰胺的WAXD分析

采用X射线衍射仪、示差扫描热分析仪及热台偏光显微镜对热致液晶聚酰胺进行了研究。DSC曲线上有明显的玻璃化转变温度(Tg)及两个熔融峰(Tm、Ti),表明聚合物具有明显的液晶性;WAXD曲线上在2θ=20°左右有一弥散的峰,在2θ10°的小角范围内观察不到任何的衍射峰,表明聚合物为向列型液晶结构;偏光显微镜下观察到了丝状粒球的向列型液晶的典型结构,更进一步支持了WAXD所得结论。     

PP/MCC/H20-g-SA木塑复合材料的制备及性能研究

以聚丙烯(PP)为基体,剑麻微晶(MCC)和轻质碳酸钙(Ca CO3)为填料,硬脂酸接枝超支化聚酯(H20-g-SA)为相容剂,经过挤出、造粒、注塑成型来制备PP/MCC/H20-g-SA木塑复合材料。采用红外光谱(FTIR)、X射线广角衍射(WAXD)、热重分析(TG)、差示扫描量热(DSC)、动态力学分析(DMA)、摆锤冲击试验机和场发射扫描电镜(SEM)等对复合材料性能进行测试及表征。结果表明,加入4%相容剂H20-g-SA改性PP/MCC复合材料比未改性体系的冲击强度和熔体质量流动速率分别高出近1倍和2倍,使得复合材料的韧性与流动性得到提高。DSC与WAXD分析表明,H20-g-SA的加入降低了体系的结晶性能。SEM表明,加入H20-g-SA提高了复合材料的界面相容性。     

水在聚乙烯醇/水体系中的状态及氢键作用

水在聚乙烯醇(PVA)中的状态直接影响PVA的热塑加工.采用DSC和Raman光谱研究了水含量对其在PVA中的状态及氢键作用的影响.结果表明:水在PVA中以3种状态存在,随水含量增加,非冻结合水比例减小,可冻结合水和自由水比例增加.通过高斯分峰可将Raman光谱水的羟基伸缩振动峰分为5种羟基振动峰叠加,分别代表多氢键结合水分子的羟基对称与反对称伸缩振动,双氢键结合水分子羟基伸缩振动,单氢键结合水分子羟基伸缩振动,无氢键或弱氢键相互作用水分子的羟基伸缩振动.水含量增加,单氢键结合与多氢键结合水分子含量增加,而双氢键结合与无氢键结合水分子含量减少.     

四川软玉猫眼的红外光谱和X射线粉晶衍射特征

通过对四川软玉猫眼进行X射线粉晶衍射(XRD)、傅立叶变换红外光谱(FTIR)分析,结果表明四川软玉猫眼主要由透闪石矿物组成.利用XRD计算的晶胞参数为α0=0.984nm～0.985nm,ь0=1.780nm～1. 782 nm,с0=0.527nm～0.528 nm,β=106.13°～106.35°.傅立叶变换红外谱带中3670cm-1附近的吸收谱带归属透闪石结构中OH伸缩振动的A带.960cm-1～1100cm-1间的谱带归属(Si4O11)的伸缩振动.600cm-1～800cm-1范围内谱带归属uaSi-O-Si振动,400cm-1～600 cm-1范围内的谱带归属(Si4O11)的弯曲振动和Mg-O伸缩振动.     

PLLA/CQD纳米复合薄膜的制备及其性能研究

聚乳酸(PLLA)具有优良的生物相容性和生物可降解性能,但其脆性大、结晶速率慢且结晶形态难控制等,限制其广泛应用.因此制备生物质碳量子点(CQD)改性PLLA.首先制备了表面含有大量羟基、尺寸在2 nm左右的CQD.研究表明,加入0.1％的CQD纳米颗粒,PLLA/CQD复合膜的结晶度明显提高了129％.有趣的是,当C...     

纤维素-丝素复合膜的制备与表征

通过NaOH/尿素/硫脲/水新型溶剂溶解原生木浆纤维素得到纤维素溶液,并与丝素溶液混合制备纤维素-丝素复合膜.利用扫描电镜、红外光谱、X-射线衍射对复合材料的结构进行表征.SEM结果表明复合材料表面粗糙,比表面积较大,可以作为潜在的生物医用材料.IR和X-衍射结果表明再生纤维素与丝素分子之间存在着强烈的氢键作用,且二者相容性较好.     

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。