Preparation method of starch-based flame-retardant polyether polyol

Abstract

The invention discloses a method for preparing flame-retardant polyether polyol by catalytically liquefying pre-gelatinized starch by taking boron phosphate as a catalyst, and belongs to the technicalfield of efficient utilization of chemical material biomass. The preparation method comprises the following steps of: taking pre-gelatinized starch as the raw material, adopting a mixed solvent of diethylene glycol, diethanol amine and glycerol as a liquefying agent and using boron phosphate as the catalyst, and carrying out reaction in a hydrothermal kettle to prepare the flame-retardant polyether polyol. The hydroxyl value of the obtained flame-retardant polyether polyol is 360.5-436.5mgKOH / g, and the liquefaction rate of starch is as high as 96.4%. The limit oxygen index of the foam prepared from the liquefied product reaches 28.9, the heat conductivity coefficient is 0.019 W / m.K, the compression strength is 206.0 kPa, the apparent density is 62.8 kg / m<3>, and the flame retardant property can be self-extinguished when the foam is away from fire. The mechanical properties are equivalent to those of polyurethane rigid foam prepared from petrochemical raw materials, and the indexes meet the requirements of the industrial standard (JG / T314-2012) and the national standard (GB10800-1989, GBT8813-2008 and GBT6343-2009) of polyurethane rigid foam composite insulation boards.

Description

technical field [0001] The invention relates to the technical field of new chemical materials and high-quality utilization of biomass, in particular to a preparation method of starch-based flame-retardant polyether polyol. Background technique [0002] Polyurethane is a general term for macromolecular compounds containing repeated carbamate groups in the main chain obtained by the reaction of polyisocyanate and dihydroxy or polyhydroxy compounds. In recent years, with the increasing shortage of petroleum resources, the price of polyether polyol, which is one of the main raw materials for the synthesis of polyurethane, has experienced a surge in price. And because the raw materials of traditional polyurethane come from the petroleum industry entirely, it is difficult to degrade and recycle the products after they are discarded, causing serious pollution to the environment. In order to alleviate the excessive dependence on the depleted petroleum resources and reduce the pollu...

AI Technical Summary

Problems solved by technology

[0007] Based on the existing polyol preparation technology, the liquefaction process using sulfuric acid and other liquid mineral acids as catalysts has problems such as catalyst disposal and equipment corrosion; the liquefaction process using solid acids as catalysts has catalyst separation and reuse problems, and the liquefaction products The prepared foam materials do not have flame retardant properties, which limits the popularization and application of products, so the development of more effective starch-based flame retardant polyether polyols has more important practical value