| With the growing shortage of crude oil resources,the price of chemical reagents of extracted from the crude oil increases rapidly,using wide variety of sources and abundant renewable resources instead of non-renewable mineral resources completely or partially,which not only effectively reduce the cost of production, but also promote the efficient use of some biomass resources.In this paper, using humic acid instead of chemical reagent of phenol to prepare phenolic foam,the initial part of the paper mainly adopts the traditional way of synthesis of phenolic resin,then according to the problem in the process of synthesis phenolic resin based humic acid exist.In this thesis,an advanced and without dehydrated technology was used to synthesize humic acidphenolic foam directly, the main research contents and conclusions are as follows:1. Replace part of phenol with humic acid, preparation of different content of humic acid phenolic resin and phenolic foam, studied the effects of humic acid content on resin and foam properties.The results showed that humic acid content is less than 25% the resin viscosity and solid content can meet the requirements of the foamable phenolic resin,and the mechanical property of the prepared foam was added humic acid have greatly improved,adding humic acid has little effect on the foam oxygen index,the humic acid based phenolic foam were flame retardant materials;when the humic acid content is 10% the foam has optimal performance,the solid content of the resin was 76.26%, free formaldehyde content is 1.94%, the viscosity is about 3000 mPa · s, and the compressive strength of the foam was 0.36 MPa, the apparent density is 0.085g/cm3, pure phenolic foam degradation rate was reduced by56.9%.2. Using paraformaldehyde instead of 37% formaldehyde solution,humic acid replace part of phenol can be directly synthesis of humic acid-phenolic resin,discussed the reaction temperature, reaction time, amount of catalyst, F/P(molar ratio of formaldehyde and phenol) effect of humic acid substituted phenol amount on thephysicochemical index of resin. By orthogonal design experiment and single factor experiment to selected the optimal reaction condition of the synthesis of resin.The results show that:the reaction temperature has the greatest influence on the viscosity of resin, reaction time has the greatest impact on the resin solid content, the amount of alkali catalyst should be larger, F/P=1.8 suitable.The amount of humic acid substituted phenol showed relatively good mechanical properties for 10~25wt%.3. Preparation of foams technology was discussed, the effects of the molar ratio of F/P, the foaming temperature, curing agent, surfactant and foaming agent amount on the properties of humic acid-phenolic foams.The results show that: the foaming temperature should not be too low, when the temperature below 65 ℃ the foaming is not completely, the temperature also should not be too high when foam curing too fast,easy to collapse of bubble, 70~75 ℃ is appropriate;Effect of physical properties of molar ratio on the foam is not gresat;With the increase of foaming agent amount foaming condition is getting better and better, but mechanical properties decreased,considering the content of foaming agent in 4wt% the foam has the best performance;with the content of curing agent increased the foam apparent density increased, the curing rate increased,ultimately determine the amount of curing agent is 15wt%; Humic acid added amount is less than or equal to 30wt% can improve the performance of foam, the addition of humic acid can effectively improve the toughness of the foam, humic acid-phenolic foam pulverization rate greatly reduced compared with pure phenolic foam, and the compressive strength also increased, the oxygen index of humic acid-phenolic foams are more than 30 belong to the flame retardant materials. |
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