环氧腰果酚/硅氧烷对酚醛树脂及泡沫性能的影响

Effects of Epoxidized Cardanol/Siloxane on Phenolic Resin Preparation and its Foam Properties

以环氧腰果酚(ECD)为酚原,替代部分苯酚,同时引入1,3-双(氨丙烷基)四甲基二硅醚(APTMDS),合成改性酚醛树脂,进而制备改性酚醛泡沫。分析APTMDS添加量一定时,ECD替代苯酚量对改性树脂的结构、游离酚含量、游离醛含量、黏度以及热稳定性的影响,研究ECD替代苯酚量对改性泡沫压缩强度、弯曲强度、易碎性能以及燃烧性能的影响。结果表明,当APTMDS添加量一定时,改性树脂体系的游离酚含量随着ECD的替代量的增加而呈下降趋势,游离醛随着ECD的替代量的增加而呈上升趋势,改性树脂体系的黏度随着ECD的替代量的增加有所上升。改性酚醛泡沫的压缩和弯曲强度有很大程度的提高,当ECD替代量为4%(wt)时,改性泡沫的压缩和弯曲强度最大,分别为0.281和0.363 MPa,与纯酚醛泡沫相比,分别提高了91.16%和62.05%。改性酚醛泡沫粉碎率有所降低,当ECD替代苯酚量为12%时,改性酚醛泡沫的粉碎率最小,19.81%,与纯酚醛泡沫相比,下降了24.13%。改性后的酚醛泡沫的阻燃性能略有下降。

Modified phenolic resins(PRs)were synthesized using epoxidized cardanol(ECD)to partially replace phenol and 1,3-bis(3-aminopropyl)tetramethyldisiloxane(APTMDS)was also introduced.The modified PRs were further used for the preparation of modified phenolic foams(PFs).Effects of ECD dosage on structure,free phenol content,free aldehyde content,viscosity and thermal stability of the modified PRs were studied under constant APTMDS dosage.Moreover,its effects on compressive and flexural strength,friability and combustion performance of the modified PFs were investigated.The results show that free phenol contents of the modified resins decrease with the increase of ECD,while free aldehyde contents and viscosity vary inversely.Compressive and flexural strength of the modified PFs are improved significantly.Maximum compressive strength(0.281 MPa)and flexural strength(0.363 MPa)are achieved when ECD dosage is 4%,which are increased by 91.16%and 62.05%when comparing with normal PF.Pulverization ratios of the modified PFs are decreased after modification.When ECD dosage is 12%,the modified PFs exhibit a minimum pulverization ratio of 19.81%which is decreased by 24.13%when compared with normal PF.Moreover,the addition of ECD and siloxane can result in slight decrease of flame retardation of the modified PFs.