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1.
刘小婧  程贤甦 《橡胶工业》2011,58(10):610-615
以酶解木质素、甲醛和间苯二胺为原料,通过正交试验制备酶解木质素-间苯二胺共聚物;以酶解木质素-间苯二胺共聚物为阻燃剂,自制微胶囊红磷为酸源,制备酶解木质素-间苯二胺共聚物/红磷/SBR阻燃复合材料,研究酶解木质素-间苯二胺共聚物用量对复合材料阻燃性能和物理性能的影响.结果表明:酶解木质素-间苯二胺共聚物的最佳工艺条件为木质素用量30 9,甲醛用量0.2 mol,间苯二胺用量0.1 mol,温度80℃,时间 3 min,氢氧化钠质量分数0.03;当酶解木质素-间苯二胺共聚物用量为60份、微胶囊红磷用量为10份,酶解木质素-间苯二胺共聚物/红磷/SBR阻燃复合材料的阻燃级别达FV-0,综合物理性能较好.  相似文献   

2.
在碱性条件下,液体木质素先经苯酚处理后替代部分苯酚对酚醛树脂进行改性,制备得到液体木质素改性酚醛树脂(LPF)胶粘剂。考察了催化剂用量(苯酚处理木质素时氢氧化钠用量)、苯酚与甲醛(P/F)的物质的量之比、聚合温度、聚合时间对LPF胶粘剂性能的影响。研究结果表明:当催化剂用量3%、n(苯酚)∶n(甲醛)=1∶1.975、聚合温度90℃、聚合时间50 min时,所制备的LPF胶粘剂的干湿胶合强度分别为3.15、1.46 MPa,较未经改性的PF胶粘剂分别提高了17.5%、8.1%,游离苯酚的含量降低至0.62%;LPF胶粘剂的游离甲醛含量为0.22%,固体含量为52.8%,黏度为125 mPa·s。红外分析结果表明,苯酚处理后的木质素可以代替苯酚与甲醛发生反应生成新的物质,该物质有可能与PF胶粘剂发生接枝共聚产生新的醚键桥接,由此也说明在制备LPF胶粘剂过程中木质素发生了化学反应。  相似文献   

3.
以木质素和碳酸钙为原料,在球磨机上以一定的转速并按照一定的配比混合湿法球磨制备了木质素-碳酸钙(Lignin-Ca CO3)复合物,并将其分别用于丁腈橡胶(NBR)和丁苯橡胶(SBR)中,共混制备了丁腈橡胶/木质素-碳酸钙(NBR/Lignin-Ca CO3)和丁苯橡胶/木质素-碳酸钙(SBR/Lignin-Ca CO3)复合材料。考察了木质素-碳酸钙(Lignin-Ca CO3)复合物的配比、木质素-碳酸钙(Lignin-Ca CO3)复合材料的硫化剂用量、硫化温度对橡胶复合材料力学性能的影响。在此基础上,选定了一个适宜的复合填料组成比例,研究了不同填料份数对橡胶复合材料的力学性能的影响。研究结果表明:丁腈橡胶/木质素-碳酸钙复合材料中当填料份数为60时,木质素与碳酸钙之间的配比为30/10,硫化剂用量为2.5 phr,硫化温度为170℃其综合性能最好,其中拉伸强度、断裂伸长率、300%定伸应力和硬度分别为18.7 MPa、774%、3.8 MPa和74 HA;丁苯橡胶/木质素-碳酸钙复合材料当填料份数为40时,当木质素与碳酸钙之间的比例为20/20,硫化剂用量为1.5 phr,硫化温度为160℃其综合性能最好,其中拉伸强度、断裂伸长率、300%定伸应力和硬度分别为8.4 MPa、706%、1.1 MPa和48 HA。  相似文献   

4.
用反向沉淀法制备酶解木质素/氢氧化镁复合材料,并研究其对丁苯橡胶(SBR)胶料的阻燃效应。结果表明:复合材料中酶解木质素包覆氧化镁,酶解木质素/氢氧化镁并用比为1∶1时,复合材料的阻燃效应较好,800℃时的质量保持率高;100份复合材料(酶解木质素/氢氧化镁并用比1∶1)的与10份微胶囊红磷配合的SBR胶料燃烧成炭性好,阻燃级别可达到FV-0,阻燃性能和物理性能好。  相似文献   

5.
脲醛改性酶解木质素对丁苯橡胶阻燃性能的影响   总被引:1,自引:0,他引:1  
以脲醛改性酶解木质素配合自制的微胶囊红磷(MRP)制得高分子膨胀阻燃剂,用傅里叶变换红外光谱和差示扫描量热法对其进行了表征,并将其添加到丁苯橡胶(SBR)中,研究了SBR的阻燃性能和力学性能。结果表明,脲醛改性酶解木质素在280℃附近出现了1个较强的吸热峰;随着改性酶解木质素或MRP用量的增加,SBR的阻燃性能提高;当改性酶解木质素用量为60份、MRP用量为10份时,或当改性酶解木质素用量为40份、MRP为12份时,SBR的阻燃级别均可达到FV-0级;SBR/改性酶解木质素/MRP共混物的燃烧残渣表面生成了连续而致密的炭层,孔洞很少且细小。当改性酶解木质素用量为40份时,SBR硫化胶具有最佳的拉伸性能;当MRP用量为10份时,SBR硫化胶的综合性能较好。  相似文献   

6.
研究类绢云母/丁苯橡胶(SBR)复合材料的硫化特性及物理性能。结果表明:添加类绢云母后的SBR胶料物理性能提高;类绢云母对SBR的补强效果优于碳酸钙、高岭土和沉淀硫酸钡等通用无机填料;偶联剂改性有利于提高类绢云母/SBR复合材料的性能,偶联剂Si69的改性效果较突出;当偶联剂Si69用量为类绢云母用量的10%时,胶料的拉伸强度和耐磨性能较好。  相似文献   

7.
利用生物基材料木质素代替部分苯酚合成生物基酚醛树脂,并将其应用到顺丁橡胶中;采用同步法制备顺丁橡胶/生物基酚醛树脂复合材料(BR/LPF),并对其形态结构、机械性能及热稳定性等进行了研究。SEM及DSC结果表明,BR/LPF形成了互穿网络结构,两相出现相分离,相畴尺寸较大。机械性能实验结果表明,BR与LPF的比例对复合材料的拉伸强度、撕裂强度、硬度、拉断伸长率等影响较大,其中以BR/LPF(80/20)复合材料综合性能最佳;LPF的构成组分对机械性能也有较大影响。TGA实验表明,BR/LPF复合材料具有较好的热稳定性,加入LPF可提高复合材料的降解温度(T50%)。  相似文献   

8.
利用木质素部分替代苯酚,三步共聚制备了木质素基酚醛树脂胶粘剂(LPF),研究了碱浓度、醛酚比、木质素添加量对LPF的粘度、固含量、游离甲醛含量、游离苯酚含量和胶合强度的影响,并采用FT-IR、13C-NMR和TG对LPF官能团结构和热固化特性进行了表征。结果表明:采用三步共聚法分步加入甲醛溶液,更有利于羟甲基化反应和后续的缩聚反应,并且可操作性好。胶粘剂的最优制备工艺为:碱的质量分数15%(以木质素和苯酚总质量为基准);醛、酚物质的量比2.0∶1;木质素添加量为苯酚物质的量分数30%。制得的LPF胶粘剂的粘度为183.2 mPa·s,固体质量分数45.05%,游离甲酵质量分数0.22%,胶合强度0.85 MPa,均达到GB/T 14732—2006要求。木质素的添加还改善了酚醛树脂的热固化特性。  相似文献   

9.
叶欣  姚鹏军  奚梅梅  张立群 《橡胶工业》2013,60(10):581-587
研究华光炭黑用量对丁苯橡胶(SBR)复合材料性能的影响,并与炭黑N330进行对比。结果表明:与炭黑N330相比,华光炭黑具有中空结构、较大的比表面积和较高的结构性;相同用量华光炭黑填充SBR胶料的门尼粘度和拉伸强度较大,导电性能和导热性能较好。随着炭黑用量的增大,两种复合材料的物理性能、导电性能和导热性能均提高。当华光炭黑用量为15份时,华光炭黑/SBR复合材料已成为导电材料。  相似文献   

10.
麦草碱木素酚化改性及其制备LPF胶粘剂工艺研究   总被引:2,自引:0,他引:2  
利用碱性条件下酚化改性的麦草碱木素代替部分苯酚制备了高木质素/苯酚比例和胶粘强度高的木质素酚醛树脂(LPF)胶粘剂.利用傅立叶红外光谱(FT-IR)和凝胶色谱(GPC)研究了麦草碱木素在碱性条件下酚化改性前后的结构变化.FT-IR分析表明,麦草碱木素发生了酚化反应,伴随着酯基的断裂和甲氧基的脱落;GPC结果显示,木质素平均分子量降低,分子量分布范围变宽.接着,研究了木质素/苯酚比例、氢氧化钠浓度、甲醛/木质素比例、酚化温度、酚化时间、缩聚温度、缩聚时间等反应工艺参数对LPF胶粘剂性能的影响,优化了麦草碱木素酚化改性制备LPF胶粘剂的反应工艺参数.最后,比较了反应工艺参数优化的LPF胶粘剂与传统PF胶粘剂的各项性能,结果显示,麦草碱木素酚化改性后代替70 % 的苯酚制备得到的LPF胶粘剂的胶粘强度与传统PF胶粘剂相近.  相似文献   

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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.  相似文献   

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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.  相似文献   

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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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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