固体多聚甲醛制备酚醛树脂及其发泡工艺研究.pdf

武汉理丁大学硕士学位论文
摘要
节能环保是当今社会的主题,建筑保温材料是备受学者青睐的研究方向。
酚醛保温材料是利用热固性酚醛树脂发泡固化而成,这种泡沫材料具有导热系
数低、阻燃性能高、低发烟率、尺寸稳定性好等特点,明显强于占据大部分市
场的聚氨酯、聚苯乙烯、聚乙烯泡沫材料,但脆性大、易粉化掉渣一直限制其
大规模的生产应用。
本论文主要利用多聚甲醛和苯酚合成酚醛树脂,优化了合成工艺,制备出
了适合发泡的酚醛树脂,并以此为主原料,加入稳泡剂、发泡剂、固化剂和添
加剂优化各成分比例和发泡工艺,制备出了性能较好的泡沫保温材料。
树脂合成实验中,探讨了反应温度、催化加用量、反应时间等实验条件对
树脂性能的影响,通过旋转粘度计测定了树脂粘度变化,称量法测试树脂固含
量的变化,混酸常温固化法测定树脂活性的变化,用FTIR分析树脂结构的变化,
平板小刀法测定树脂凝胶化时间,结果表明:催化剂NaOH用量为苯酚用量1%
时,树脂活性最高;反应时间和反应温度的延长和升高会使树脂的固含量和粘
度升高,反应后期变化更为明显,85℃下反应120~180min得到树脂粘度在
5000 npa 's-800o0pas;羟甲基指数随时间延长先增大(最高可达1.45)后降
低并维持在一定范围(1.2左右),85℃下反应超过300min,羟甲基指数和凝胶
化时间明显降低;不同树脂粘度随温度升高粘度减小,低于25℃时粘度增加明
显;树脂在常温放置一周,性能变化不大,大粘度树脂变化略微明显。
酚醛树脂泡沫制备的实验中,探讨了不同粘度树脂、稳泡剂、发泡剂、固
化剂和添加剂乙二醇对泡沫体固化成型时间、吸水率、垂直拉伸强度、密度及
表观质量等性能的影响,结果表明:室温下树脂粘度在500080opas时泡
沫体性能较好;稳泡剂DC-193:EL-40=3:1,总量为2~5%时;发泡剂用具有沸
程的石油醚(30-60℃),用量为5~6%;固化剂苯磺酸:对甲苯磺酸=3:1,用量
为3-5%制备泡沫的性能较好,体积密度为50-60Kgym3的泡沫体,吸水率在
68%,压缩强度在018-0.21Mpa,导热系数约为0.032w(m?k),添加剂乙二醇
的加入有利于降低树脂粘度、提高泡沫的拉伸强度,对泡孔结构有一定的影响,
综合考虑乙二醇用量为4~8%较为适宜。
关键词:多聚甲醛,酚醛树脂,酚醛泡沫,发泡工艺,性质
武汉理工大学硕士学位论文
Abstract
Energy saving and environmental protection is the theme of today,'s society, and
building insulation material is the hot research area for scholars. the phenolic
insulation foam is made use of the thermosetting phenolic resin which is cured and
foamed, this foam has a low thermal conductivity, excellent resistance to fiery, low
smoke by fired, good dimensional stability and other characteristics, better than the
polyurethane, polystyrene, polyethylene foam, which has occupied much market. It
has been limited to large-scale production applications for that it is brittle, and easy
to chalk and slag
In this paper, phenolic resin used for making foam is synthesized by
paraformaldehyde and phenol and the synthesis process is optimized. The better
performance of the foam insulation is based on this raw material, adding a stable
foam, foaming agents, curing agents and toughener, Optimizing the proportion of
each component and foaming process
The effect of the reaction temperature, the catal ytic plus the amount of reaction
time and other experimental conditions to the resin performance is studied in the
synthesis experiments. The change of the resin viscosity is tested using the viscosity
Determination, the solid content is tested using the weighing method, the resin
activity is tested by mixed acid at room emperature, the changes in the structure of
resin is monitored by FTR, and the resin gel time is also tested using tablet knife
method. The experimen al results shows that the resin activity is the best with 1%o( o
phenol) catalyst NAOH, and extending reaction time and increasing reaction
temperature make the solid content and viscosity of the resin increased and more
obvious changes occurred in later reaction Resin viscosity is 5000mpas-8000mpa
s with reaction ime 120180min at85. Hydroxymethyl index increased(up to
1 45 and then decreased and maintained at a certain range(around 1.2), The reaction
more than 300min, hydroxymethyl index, and the gel time decreased
significantly Resin viscosity reduce with temperature increases, and performances
exponential growth with temperature less than 25 C. The performance of resin