共查询到19条相似文献,搜索用时 125 毫秒
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以蜡质玉米淀粉为主要原料、聚乙烯醇(PVA)为保护胶体,在反应过程中加入酸解催化剂[盐酸(HCl)]、氧化剂和引发剂[过硫酸铵(APS)],制得酸解氧化淀粉;然后将其与醋酸乙烯酯(VAc)、丙烯酸乙酯(EA)接枝共聚后,制得新型环保复合淀粉胶粘剂。研究结果表明:采用单因素试验法优选出接枝反应的最佳工艺条件是HCl浓度为2.0 mol/L、V(VAc)=40 mL、V(VAc)∶V(EA)=3∶1、接枝反应温度为70℃、w(淀粉乳液)=20%、w(APS)=1.2%和w(PVA)=40%(均相对于淀粉干基质量而言),此时酸解氧化淀粉胶粘剂在外观、流动性、木材污染性和粘接强度等方面均优于双醛淀粉胶粘剂和PVAc(聚醋酸乙烯酯)白乳胶。 相似文献
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氧化淀粉基水性胶粘剂的研究 总被引:3,自引:2,他引:1
以过硫酸钾-亚硫酸氢钠(KPS-NaHSO3)为引发剂,在木薯氧化淀粉上接枝苯乙烯(St)和丙烯酸丁酯(BA),并引入功能单体丙烯酸(AA),采用无皂聚合法合成了氧化淀粉基水性胶粘剂。考察了引发剂用量、单体与氧化淀粉配比、单体配比、功能单体用量、聚乙烯醇(PVA)用量和反应温度对胶粘剂性能的影响,并对接枝共聚物进行了红外光谱(FT-IR)表征。实验结果表明,当w(引发剂)=1.8%、m(单体)∶m(氧化淀粉)=3.0∶1、m(St)∶m(BA)=1.75∶1、w(AA)=2.0%和w(PVA)=3%~4%时,所制备的胶粘剂的综合性能最佳,其剥离强度为23.15 N/mm、拉伸强度为0.92 MPa。 相似文献
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以VAE[醋酸乙烯酯(VAc)-乙烯共聚物]为种子乳液、聚乙烯醇(PVA)为保护胶体、叔碳酸乙烯酯(VoeVa10)为VAc的共聚单体、OP-10为乳化剂、己二酰肼(ADH)/双丙酮丙烯酰胺(DAAM)为交联体系和叔丁基过氧化氢/甲醛次硫酸钠为氧化还原型引发剂,采用种子乳液聚合法制备了VAc/VoeVa10/DAAM共聚乳液;然后在反应后期加入后交联剂(ADH),得到改性聚醋酸乙烯酯(PVAc)乳液。结果表明:当w(PVA1788+PVA1799)=3%、m(PVA1788)∶m(PVA1799)=1∶1、m(VoeVa10)∶m(VAc)=(10~15)∶100、w(氧化剂)=0.3%、w(VAE)=10%、w(OP-10)=2%、m(ADH)∶m(DAAM)=(0.5~1.5)∶1.0且w(DAAM)=2%时,相应乳液具有优异的耐水性和稳定性,并且其涂膜柔韧性和粘接性能俱佳。 相似文献
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首先用双氧水氧化木薯淀粉,然后用乙酸乙烯酯(VAc)对氧化淀粉进行接枝共聚改性,制备出木薯淀粉基木材胶粘剂。采用单因素试验法考察了木薯淀粉的氧化时间、双氧水掺量、过硫酸铵(APS)掺量以及VAc/木薯淀粉质量比对木薯淀粉基木材胶粘剂剪切强度和黏度的影响。研究结果表明:当氧化时间为1.0 h、V(双氧水)=3 m L、m(APS)=0.3 g和m(VAc)∶m(木薯淀粉)=1.00∶1时,相应的木薯淀粉基木材胶粘剂的粘接性能相对最好,其干态、湿态剪切强度分别为3.25、1.26 MPa。 相似文献
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环保耐水型木材用胶粘剂的研究 总被引:3,自引:0,他引:3
以过硫酸铵为引发剂制备低相对分子质量的聚丙烯酰胺,以次氯酸钠(NaClO)为氧化剂对淀粉进行氧化处理,然后将两者进行缩合反应得到聚丙烯酰胺接枝淀粉胶粘剂的主剂;最后以2-甲基氮丙啶为交联剂制备了环保耐水型木材用胶粘剂。采用傅里叶红外光谱(FT-IR)法和X射线衍射(XRD)法对中间体和胶粘剂进行了表征。实验结果表明,当w(交联剂)=3%(为淀粉胶主剂干胶的质量分数)、交联时间为3 h和w(丙烯酰胺)=7.5%(相对于淀粉的质量分数)时,制得胶粘剂的胶合强度达到5.30 MPa,耐水时间达33 h。 相似文献
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Hamed Peidayesh Zahed Ahmadi Hossein Ali Khonakdar Majid Abdouss Ivan Chodk 《Polymer International》2020,69(3):317-327
The poor mechanical properties and high water solubility of biodegradable thermoplastic starch (TPS) represent the main disadvantages of TPS in many applications. In this work, TPS film was prepared from a water solution of corn starch modified by 5 wt% dialdehyde starch (DAS) as crosslinking agent and 3 wt% montmorillonite (MMT) as reinforcing additive. Interactions occurring in the TPS films were investigated by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, XRD, DSC, dynamic mechanical thermal analysis (DMTA) and TGA. The results obtained fom FTIR spectroscopy and DSC suggest the formation of hydrogen bond interactions between the hydroxyl group of starch, DAS, the MMT layers and glycerol. DMTA indicated that the relaxation of films with DAS and MMT appears in a higher and broader temperature range due to the starch backbone stiffness; the extreme increase in the storage modulus confirmed the suggested interactions. The determination of the weight loss of the films in water indicated a significant increase of the water resistance of TPS due to incorporation of DAS and MMT. Changes in mechanical properties of the films containing DAS and clay were determined, showing a substantial increase in tensile strength from 2.7 to 6.7 MPa, while Young's modulus increased by 15 times for TPS modified with 5% DAS and 3% MMT. Therefore, the outcomes of this study confirmed that DAS is a suitable biomacromolecule crosslinker for starch and can significantly enhance TPS and TPS/MMT properties. © 2019 Society of Chemical Industry 相似文献
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Preparation of a new dialdehyde starch derivative and investigation of its thermoplastic properties 总被引:1,自引:0,他引:1
Shui-Dong Zhang Xiu-Li Wang Yu-Rong Zhang Ke-Ke Yang Yu-Zhong Wang 《Journal of Polymer Research》2010,17(3):439-446
In order to obtain thermoplastic starch plastics with improved properties, a novel method of starch modification was developed
in this study. Starch derivatives were prepared using the following procedures: pea starch was first oxidized to make dialdehyde
starch (DAS) by sodium periodate under mild conditions, and this was then acetalized with glycol to give Gly-ADS. The modified
starch was characterized by FT-IR, 1H-NMR, TG, DSC, and XRD. The TG curves indicated that the thermal stability of Gly-ADS was better than that of DAS. The glass
transition temperature of Gly-ADS with 95% carbonyl content (Gly-ADS95) was 97 °C by DSC. Although the intrinsic viscosity
of DAS was less than that of pea starch, thermoplastic Gly-ADS (TPGly-ADS) exhibited good mechanical properties. The influence
of moisture absorption on the mechanical properties of TPGly-ADS was also investigated. The results showed that TPGly-ADS
possesses improved water resistance: the highest moisture absorption of TPGly-ADS95 was about 11%, and the tensile strength
and the elongation at break were 18.1–14.6 MPa and 5.3–18%, respectively. 相似文献
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改性淀粉基木材用环保胶粘剂的合成研究 总被引:5,自引:1,他引:4
对淀粉进行糊化、氧化处理后,与聚乙烯醇(PVA)接枝反应制得胶粘剂主剂,然后分别以三聚氰胺甲醛树脂(MF)、聚氨酯(PU)预聚体作为胶粘剂主剂的改性剂,制得了木材用胶粘剂。探讨了各种原料的用量、反应条件及改性剂种类等对胶粘剂性能的影响。结果表明:胶粘剂适宜的制备工艺条件为淀粉8.0g,PVA12.0g,蒸馏水100mL,氧化剂(次氯酸钠)0.16g,引发剂(过硫酸钾)0.14g,乳化剂OP-10和十二烷基苯磺酸钠(SDS)各1.0g,改性剂12.0g;淀粉糊化温度85℃,pH值9~10,淀粉预糊化时间20min;氧化时间30min,接枝反应温度95℃,pH值2~3,接枝反应时间20min;改性反应温度60℃,pH值6~7,改性反应时间1.5h。由该胶粘剂压制的层压板,其粘接强度(1.00~1.25MPa)和甲醛释放量(≤0.5mg/L)等指标符合GB/T5849-2006标准要求。 相似文献
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