间十五烷基酚对酚醛泡沫的改性

Reasearch on 3-pentadecyl-phenol Modified Phenolic Foam

选用间十五烷基酚取代部分苯酚对可发性酚醛树脂进行了分子结构改性,成功制备了改性酚醛树脂并对其进行发泡固化,得到间十五烷基酚改性酚醛泡沫塑料。通过傅里叶变换红外光谱,核磁共振波谱的氢谱和碳谱对改性树脂进行了表征。结果表明,间十五烷基苯酚成功地改变了酚醛树脂的分子结构,在酚醛树脂结构中接入了长烷基链;酚醛树脂酚羟基临位点交联密度下降,对位点交联密度上升;苯环刚性下降。通过对泡沫塑料表观密度、吸水率、弯曲强度、弯曲挠度和压缩强度的测试研究了间十五烷基酚用量对泡沫塑料性能的影响。结果表明,在间十五烷基酚用量为酚总质量的5%～25%范围内,与普通酚醛泡沫塑料相比,其改性的酚醛泡沫密度均低于0.04g/cm3,吸水率下降至4%～5%,弯曲强度和压缩强度最大可达0.32MPa和0.2MPa,弯曲挠度最大可提高300%,泡沫塑料的韧性得到大幅提升。

3-pentadecyl-phenol was used for replacing partial phenol to modify the molecular structure of the foamable phenolic resin,the modified phenolic resin was successfully prepared and then foamed and cured,so the 3-pentadecyl-phenol modified phenolic foam was gained.Fourier transform infrared spectroscopy,1 H NMR and 13C NMR spectra of nuclear magnetic resonance spectra were used to characterize the modified resin.The results show that the 3-pentadecyl-phenol successfully modifies the molecular structure of the phenolic resin,and the long alkyl chain is inserted into the phenolic resin structure;the crosslink density of the phenolic hydroxyl group at the ortho-position decreases,the crosslink density at the para-position increases;benzene ring rigidity decreases.The modified phenolic foam was tested by its apparent density,water absorption rate,compressive strength,bending strength and deflection for studying the effects of 3-pentadecyl-phenol content on the properties of the modified foam.The results show that,when the 3-pentadecyl-phenol content ranges from 5%to 25%of total mass of phenol,compared with the common phenolic foam,the density of the modified phenolic foam is less than 0.04 g/cm^3,the water absorption rate is reduced to 4%-5%,the maximum values of the bending and compressive strength are 0.32 MPa and 0.2 MPa respectively,the bending deflection can be increased by 300%furthest,which indicates the toughness of the foam is improved obviously.