Biomass-based flame retardant polyurethane foams and preparation method thereof

Abstract

The invention discloses biomass-based flame retardant polyurethane foams and a preparation method thereof. The method comprises the following steps of: (1) performing first contact reaction on a straw lignin material, polyol and an acid catalyst for 1 to 4 hours at 100 to 135 DEG C, adding starch, and performing second contact reaction to obtain modified lignin; (2) performing third contact reaction on a phosphoric acid and pentaerythritol for 0.5 to 5 hours at 100 to 180 DEG C, adding polyether polyol, ammonium polyphosphate and melamine into a product of the third contact reaction, and performing fourth contact reaction for 0.5 to 4 hours at 100 to 180 DEG C to obtain a flame retardant; and (3) uniformly mixing the modified lignin, the flame retardant, the polyether polyol, an amine catalyst and a foaming agent, adding isocyanate according to an isocyanate index of 1 to 1.4 for fifth contact reaction, and curing a product of the fifth contact reaction. The biomass-based flame retardant polyurethane foams prepared by the method have high flame retardant properties and mechanical properties.

Description

technical field [0001] The invention relates to a preparation method of a biomass-based flame-retardant polyurethane foam, and a biomass-based flame-retardant polyurethane foam prepared by the method. Background technique [0002] As people's awareness of the environmental crisis and resource crisis continues to deepen, the development of new natural polymer materials such as lignin and starch has been paid more and more attention. Lignin and starch belong to natural polymer compounds, which are huge reserves and renewable organic resources, and widely exist in plants. Due to its low price and superior performance, polyurethane has become one of the fastest-growing varieties in the modern polymer industry. Since lignin and starch have multiple functional groups such as hydroxyl groups, they can replace petroleum-based chemicals (such as petroleum-based polyols) after development, and become an important source of organic compounds for the synthesis of polymer materials such...

AI Technical Summary

Problems solved by technology

However, the reactivity of lignosulfonic acid or its partially neutralized salt in this method is low, and its hydroxyl group cannot fully polymerize with polyisocyanate, and most of the lignin components can only exist in the final form as fillers. In the prepared polyurethane, therefore, on the one hand, the purpose of replacing petroleum-based polyols with lignin components cannot be realized; Poor combination with polyurethane

In addition, no flame retardant is added in this method, so that the flame retardancy of polyurethane prepared by this method is relatively poor

Although some additives that can be added as flame retardants have been disclosed in the prior art, for example, halogen-containing flame retardants and phosphorus-containing flame retardants, the halogen-containing flame retardants include pentabromodi Phenyl ether and dibromophenyl glycidyl ether. The phosphorus-containing flame retardants are mainly based on ammonium polyphosphate (such as Exolit AP), based on organic phosphorus compounds (such as Exolit OP) or based on red phosphorus (such as Exolit RP) and other phosphorus-containing flame retardants, however, the polyurethane prepared by using a halogen-containing flame retardant is more toxic when burned, and the reactivity of the polyurethane prepared by using a phosphorus-containing flame retardant is low, so it cannot be used with Polyurethane undergoes a polymerization reaction, resulting in poor flame retardancy of the resulting polyurethane

Images