Preparation method of rigid polyurethane foam

Abstract

The invention discloses a preparation method of rigid polyurethane foam, relates to the field of polyurethane industry, and particularly relates to a preparation method of rigid polyurethane foam. The preparation method comprises the following steps of the preparation of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate: mixing 1-methylimidazole, n-butyl bromide and potassium tetrafluoroborate, adding an obtained first mixture into a 100mL of flask, agitating the first mixture, making the first mixture react for 3h to 3.5h at a constant temperature of 80 DEG C, cooling an obtained second mixture to a room temperature, diluting the second mixture by using acetonitrile, depositing an obtained third mixture by using potassium bromide, filtering an obtained fourth mixture, moving filtrate into a rotary evaporator, pressurizing the filtrate to remove the acetonitrile, and carrying out vacuum drying for 8h at 80 to 85 DEG C; the preparation of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate: under the protection of nitrogen, dropwise adding n-butyl bromide into 1-methylimidazole, and agitating an obtained fifth mixture. According to the preparation method, the high heat stability of the ionic liquid is utilized; the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate and 1-butyl-3-methylimidazolium hexafluorophosphate is prepared, and is applied to polyurethane rigid foam as flame retardants. Not only are the defects that a phosphorus flame retardant is high in volatility and relatively low in heat resistance overcome, but also the defect that a halogen flame retardant is large in fuming amount is overcome.

Description

technical field [0001] The invention relates to the field of polyurethane industry, in particular to a method for preparing rigid polyurethane foam. Background technique [0002] Polyurethane foam has incomparable advantages in thermal insulation, heat insulation, sound insulation, etc., and is widely used in various large-scale public facilities, high-end hotels, restaurants.... But just like other polymer materials. Polyurethane foam without flame retardant treatment is flammable in the air, and its limiting oxygen index (LOI) is only about 18. It is easy to be ignited in the presence of a fire source, and the flame spreads rapidly, accompanied by a large amount of smoke. Therefore, the development of flame retardant technology has received more and more attention. At present, there are many reports on flame retardant methods of polyurethane materials. Commonly used flame retardants are divided into additive flame retardants and reactive flame retardants. There are many ...

AI Technical Summary

Problems solved by technology

But just like other polymer materials. Polyurethane foam without flame retardant treatment is flammable in the air, and its limiting oxygen index (LOI) is only about 18. It is easy to be ignited in the presence of a fire source, and the flame spreads rapidly, accompanied by a large amount of smoke.