文献类型：专利

英文题名：Preparation of flame retardant insulation modified melamine formaldehyde rigid foam board for preparing of e.g. insulation material, involves mixing melamine formaldehyde resin precursor with emulsifier, foam stabilizer and foaming agent

作者：LANG M;WANG J

机构：[1]UNIV EAST CHINA SCI & TECHNOLOGY

申请号：CN107556514-A

申请日：2017-09-12

公开日：2018-01-09

语种：英文

收录：DERWENT

摘要：NOVELTY - Preparation of modified melamine formaldehyde rigid foam board, involves (i) preparing polytetrahydrofuran-modified melamine, (ii) adding polytetrahydrofuran-modified melamine and formaldehyde solution, mixing paraformaldehyde, adjusting pH, reacting, when solution becomes clear, adjusting pH with hydrochloric acid, reacting, when reaction solution appears cloud point, dewatering to obtain foamed melamine formaldehyde resin precursor, (iii) mixing precursor, emulsifier, foam stabilizer, foaming agent, curing agent, nucleating agent and infrared absorber, stirring, foaming and curing. USE - Preparation of flame retardant insulation modified melamine formaldehyde rigid foam board used for preparation of insulation materials, flame retardant materials or heat-resistant materials (all claimed). ADVANTAGE - The melamine formaldehyde rigid foam board has excellent mechanical properties and fireproof properties, and has the characteristics of lightweight, heat preservation, heat insulation, low thermal conductivity, microscopic hole regularity and high opening rate, and also the rigid foam board does not have dross characteristics. DETAILED DESCRIPTION - Preparation of flame retardant insulation modified melamine formaldehyde rigid foam board, involves (i) mixing melamine with a modifier in methanol as solvent, and adjusting the pH to 5.0-6.0 with oxalic acid or hydrochloric acid, then reacting at 80-90 degrees C for 30-90 minutes to obtain modifier-modified melamine which is polytetrahydrofuran-modified melamine where modifier is polytetrahydrofuran, and the polytetrahydrofuran has molecular weight of 1000 and is added in a proportion of 5-15 wt.% of melamine, (ii) adding polytetrahydrofuran-modified melamine and formaldehyde solution, mixing paraformaldehyde where molar ratio of melamine to single formaldehyde molecule is 1:(2-3) and mass fraction of formaldehyde solution is 37%, using methanol as solvent, and adjusting the pH to 8.0-10.0 with sodium hydroxide, reacting at 80-90 degrees C, and when the solution becomes clear, adjusting the pH to 5.0-6.0 with hydrochloric acid, reacting at 50-60 degrees C and when the reaction solution appears cloud point, then dewatering to a viscosity of 500-2000 mPa.second, and obtaining foamed melamine formaldehyde resin precursor, (iii) mixing melamine formaldehyde resin precursor, emulsifier, foam stabilizer, foaming agent, curing agent, nucleating agent and infrared (IR) absorber in a mass ratio of 100:(2-5):(1-4.5):(4-8):(3-6):(1-2):(0.5-2.0), stirring uniformly, when the mixture appears uniform foam, and placing the mixture in a mold, foaming at 50-70 degrees C, and curing at 80-120 degrees C to obtain modified melamine formaldehyde rigid foam board.