共查询到19条相似文献,搜索用时 86 毫秒
1.
2.
本文对室内装饰用的人造板的甲醚释放规律进行研究。试验结果表明,人造板甲醛释放量随温度升高而增加;随含水率增加而增大:随人造板放置时间增长,而逐渐降低。人造板封边与否,则明显影响甲醛释放量。本论文的研究可以为室内甲醛污染的治理提供依据。 相似文献
3.
4.
刨花板是人造板的一个品种,它以木材加工后的废料,采伐剩余物和小径材,甚至植物秸杆如棉花杆为原料,经粉碎、干燥、施胶、压制而成。是节约木材、提高木材利用率的重要途径。 刨花板使用脲醛树脂作粘合剂,脲醛树脂属于甲醛系列胶粘剂。它以尿素和甲醛 相似文献
5.
6.
7.
8.
9.
现今家具种类样式繁多,GB 18584-2001《室内装饰装修材料木家具中有害物质限量》对于试件制备,要求较为灵活,在实际甲醛检测过程中受检验人员的影响较大。故本文依据GB 18584-2001中关于木制家具甲醛释放量干燥器法测定方法,单就家具生产中所用中密度饰面板分析研究试件在不同封边比例下甲醛释放量的变化趋势。结果表明,试件封边比例在50%时,既能减小木质材料自身的甲醛含量不均匀对于检测结果的影响,又能模拟木家具在实际中的使用情况,减小人为因素对于检测结果的影响。 相似文献
10.
11.
12.
13.
介绍了脲醛树脂胶粘剂的现状和存在问题。分析了游离甲醛的产生机理,并介绍了目前改性脲醛树脂胶粘剂的各种方法。 相似文献
14.
低游离甲醛含量脲醛树脂胶粘剂的研究 总被引:6,自引:0,他引:6
研究了低游离甲醛含量脲醛树脂胶粘剂的合成新工艺,探讨了甲醛/尿素摩尔比、反应温度、pH值、以及加料的顺序等因素对脲醛树脂综合性能的影响,并采用三聚氰胺进行了改性,以提高耐水性及进一步降低产品中游离甲醛量。采用乙酰丙酮分光光度法测定了所制备胶粘剂中的甲醛含量。实验结果表明本工艺合成的脲醛树脂游离甲醛含量低、综合性能好,符合绿色环保的要求。 相似文献
15.
利用氨及氨的衍生物与甲醛发生加成反应,生成一种常温下稳定的化合物,从而固定住游离的挥发性甲醛。选用无机铵盐(硫酸铵)和有机胺(二乙胺、二乙烯三胺、三乙烯四胺)作为固定剂。在室温下,固定剂溶液pH=11,溶液物质的量配比分别为硫酸铵与二乙胺1∶3、硫酸铵与二乙烯三胺1∶2.5和硫酸铵与三乙烯四胺1∶2。将固定剂溶液喷洒在板材表面,形成的液膜阻止了甲醛的释放,且溶液还可以渗入到板材内部,反应掉板材内游离的甲醛,形成稳定的化合物。溶液未干燥的状态下甲醛固定率为95%,溶液干燥后甲醛固定率大于95%。使用甲醛固定剂后,挥发性甲醛释放量不到原来的5%,基本切断了室内空气甲醛污染的来源。 相似文献
16.
低游离甲醛含量脲醛树脂胶粘剂的合成工艺研究 总被引:8,自引:4,他引:4
研究了在弱酸-弱碱-弱酸条件下,加入改性剂合成脲醛(UF)树脂胶的工艺过程。实验结果表明,甲醛与尿素的配比[即n(F)/n(U)比值]、体系pH值、尿素的加料方式和改性剂对UF树脂胶中游离甲醛的含量和胶合强度有很大的影响;当n(F)/n(U)=1.06、缩聚反应阶段体系的pH值为4.75~4.80、尿素分3批加入、反应温度为90℃、加入适量的聚乙烯醇(PVA)和三聚氰胺改性剂时,制得的UF树脂胶中游离甲醛的含量不大于0.10%(符合GB/T14 074.16-1993标准中的指标要求)、粘接强度为4.70 MPa且综合性能优良。 相似文献
17.
18.
Marzieh Gangi Taghi Tabarsa Sima Sepahvand 《Journal of Adhesion Science and Technology》2013,27(13):1407-1417
The aim of this work is to evaluate performances of tannin-based resins designed as adhesive in the plywood production. For this purpose, a part of phenol formaldehyde (PF) and melamine formaldehyde (MF) in the classic adhesive formulation was replaced by tannin. The physical properties of the formulated resins (rheological characterization, etc.) were measured. In order to analyze the mechanical performance of tannin-based resins, plywood panels were produced and the mechanical properties including tensile strength wood failure and three-point bending strength were investigated. The performance of these panels is comparable to those of plywood panels made by commercial PF and MF. The results showed that the plywood panels bonded with tannin–PF (PFT) and tannin–MF (MFT) resins exhibited better mechanical properties in comparison to the plywood panels made of commercials PF and MF. The introduction of small properties of tannin in PF and MF resins contribute to the improvement of the water performance of these adhesives. The formaldehyde emission levels obtained from panels bonded with tannin-based resins were lower than those obtained from panels bonded with control PF and MF. Although there are no actual reaction at all between PF, MF, and tannin, addition of tannin significantly improves the water resistance of PF and MF resins. This is a novel finding that manifests the possibility of replacing a convention PF and MF resins by tannin. Modified adhesive is one of the goals in the plywood production without changing any of their production conditions with improvement to their overall properties. 相似文献