Preparation method of slow-rebound polyurethane foam

Abstract

The invention relates to a preparation method of slow-rebound polyurethane foam. The method is characterized by including the following steps of firstly, heating AA and DEG for esterification polycondensation reaction, and conducting reaction till the acid value is 20-25 mgKOH / g; secondly, adding oxidized carbon black containing carboxyl and hydroxyl functional groups to the product obtained in the first step, conducting vacuumizing, conducting reaction till the acid value is smaller than or equal to 2.0 mgKOH / g, and increasing the vacuum degree and continuing to conduct reaction to obtain DEG polyhydric alcohols modified by oxidized carbon black and terminated with hydroxyl groups, namely modified DEG polyhydric alcohols; thirdly, adding chain extender, catalyst, H2O and polyether triols to the product obtained in the second step to be evenly mixed to prepare a component A for preparing polyurethane foam; fourthly, conducting heating polymerization on diisocyanate and polyether triols to prepare a component B for preparing polyurethane foam, wherein diisocyanate is excessive; fifthly, evenly mixing the component A and the component B for preparing polyurethane foam according to the molar ratio of hydroxyl groups to isocyanate groups being 1.0:1.05, coating a PET film with the mixture according to the thickness of 0.1-0.4 mm, and conducting heating and curing to obtain the slow-rebound polyurethane foam.

Description

technical field

[0001] The invention relates to polyurethane foaming, in particular to a method for preparing slow-rebound polyurethane foam. Background technique

[0002] Polyurethane foam materials have been applied in many fields of people's daily life, from sofa cushions to car seats, from earphone covers to heat insulation and shock absorption materials, polyurethane foam materials can be seen almost everywhere. Polyurethane foam materials are generally two-component polyurethane products. One group is a mixture of polyol, catalyst, chain extender, water or a mixture of polyol, chain extender prepolymer, water, and catalyst; the other The component is isocyanate or modified isocyanate, and the modification methods include dimerization, trimerization, polyol modification, and chain extender modification. Among them, water, as the gas source in the foaming process, can chemically react with isocyanate to form biuret, polyurea, etc., and release CO2, while the holes forme...

Examples

preparation example Construction

[0024] The invention provides a kind of preparation method of slow resilience polyurethane foam, it comprises the following steps:

[0025] (I) Heat AA and DEG for esterification and polycondensation reaction until the acid value is 20~25mgKOH / g;

[0026] (II) Add oxidized carbon black containing carboxyl and hydroxyl functional groups to the product of step (I), vacuumize, react until the acid value is ≤ 2.0mgKOH / g, increase the vacuum to continue the reaction to obtain modified oxidized carbon black, hydroxyl Ending DEG polyols, i.e. modified DEG polyols;

[0027] (Ⅲ) Add chain extender, catalyst, H to the product obtained in step (II) 2 O, polyether trihydric alcohol, mix as the A component of polyurethane foam after mixing;

[0028] (Ⅳ) After thermal polymerization of diisocyanate and polyether triol, it is used as component B for the preparation of polyurethane foam, wherein the diisocyanate is excessive;

[0029] (Ⅴ) After mixing component A and component B of polyure...

Embodiment 1

[0035] (I) React AA1461.4g with DEG 1226.1g (the amount of DEG added is 0.839 times the amount of AA added by weight) at 210°C for 5h, until the acid value is 25mgKOH / g;

[0036] (II) Add 26.87g (1wt%) of ozone-oxidized carbon black to the product of step (I) to continue the reaction for 4 hours, and vacuumize to remove the water produced by the reaction until the acid value is less than or equal to 2.0mgKOH / g , increase the vacuum until the acid value reaches 0.5mgKOH / g, and the hydroxyl value reaches 35mgKOH / g, so as to obtain DEG polyols modified by oxidized carbon black and terminated by hydroxyl groups, that is, modified DEG polyols;

[0037] (Ⅲ) 500g modified DEG polyol, 100g polyether triol (molecular weight 550), chain extender ethylene glycol 9g (1.5wt%), deionized water 4.8g (0.8wt%), catalyst caprylic acid Bismuth 0.0282g, catalyst triethyldiamine 0.0318g (the weight ratio of the two catalysts is 47:53) was mixed with a high-speed mixer at room temperature for 1.5h,...

Embodiment 2

[0041] (I) React AA1461.4g with DEG 1237.36g (the amount of DEG added is 0.847 times the amount of AA added by weight) at 210°C for 5h, until the acid value is 24mgKOH / g;

[0042] (II) Add 40.31g (1.5wt%) of carbon black oxidized by strong oxidizing acid to the product of step (I) to continue the reaction for 4 hours, and vacuumize to remove the water produced by the reaction until the acid value is ≤ 2.0mgKOH / g, increase the vacuum until the acid value reaches 0.4mgKOH / g, and the hydroxyl value reaches 34mgKOH / g, to obtain DEG polyols modified by oxidized carbon black and terminated with hydroxyl groups, that is, modified DEG polyols;

[0043] (Ⅲ) 500g modified DEG polyol, 100g polyether triol (molecular weight 600), 7.8g (1.3wt%) chain extender 1,3-propanediol, 3.6g (0.6wt%) deionized water, catalyst 0.0282g of bismuth octadecanoate and 0.0318g of catalyst triethylamine (the weight ratio of the two catalysts is 47:53) were mixed with a high-speed mixer at room temperature fo...

technical field

[0001] The invention relates to polyurethane foaming, in particular to a method for preparing slow-rebound polyurethane foam. Background technique

[0002] Polyurethane foam materials have been applied in many fields of people's daily life, from sofa cushions to car seats, from earphone covers to heat insulation and shock absorption materials, polyurethane foam materials can be seen almost everywhere. Polyurethane foam materials are generally two-component polyurethane products. One group is a mixture of polyol, catalyst, chain extender, water or a mixture of polyol, chain extender prepolymer, water, and catalyst; the other The component is isocyanate or modified isocyanate, and the modification methods include dimerization, trimerization, polyol modification, and chain extender modification. Among them, water, as the gas source in the foaming process, can chemically react with isocyanate to form biuret, polyurea, etc., and release CO2, while the holes forme...

Examples

preparation example Construction

[0024] The invention provides a kind of preparation method of slow resilience polyurethane foam, it comprises the following steps:

[0025] (I) Heat AA and DEG for esterification and polycondensation reaction until the acid value is 20~25mgKOH / g;

[0026] (II) Add oxidized carbon black containing carboxyl and hydroxyl functional groups to the product of step (I), vacuumize, react until the acid value is ≤ 2.0mgKOH / g, increase the vacuum to continue the reaction to obtain modified oxidized carbon black, hydroxyl Ending DEG polyols, i.e. modified DEG polyols;

[0027] (Ⅲ) Add chain extender, catalyst, H to the product obtained in step (II) 2 O, polyether trihydric alcohol, mix as the A component of polyurethane foam after mixing;

[0028] (Ⅳ) After thermal polymerization of diisocyanate and polyether triol, it is used as component B for the preparation of polyurethane foam, wherein the diisocyanate is excessive;

[0029] (Ⅴ) After mixing component A and component B of polyure...

Embodiment 1

[0035] (I) React AA1461.4g with DEG 1226.1g (the amount of DEG added is 0.839 times the amount of AA added by weight) at 210°C for 5h, until the acid value is 25mgKOH / g;

[0036] (II) Add 26.87g (1wt%) of ozone-oxidized carbon black to the product of step (I) to continue the reaction for 4 hours, and vacuumize to remove the water produced by the reaction until the acid value is less than or equal to 2.0mgKOH / g , increase the vacuum until the acid value reaches 0.5mgKOH / g, and the hydroxyl value reaches 35mgKOH / g, so as to obtain DEG polyols modified by oxidized carbon black and terminated by hydroxyl groups, that is, modified DEG polyols;

[0037] (Ⅲ) 500g modified DEG polyol, 100g polyether triol (molecular weight 550), chain extender ethylene glycol 9g (1.5wt%), deionized water 4.8g (0.8wt%), catalyst caprylic acid Bismuth 0.0282g, catalyst triethyldiamine 0.0318g (the weight ratio of the two catalysts is 47:53) was mixed with a high-speed mixer at room temperature for 1.5h,...

Embodiment 2

[0041] (I) React AA1461.4g with DEG 1237.36g (the amount of DEG added is 0.847 times the amount of AA added by weight) at 210°C for 5h, until the acid value is 24mgKOH / g;

[0042] (II) Add 40.31g (1.5wt%) of carbon black oxidized by strong oxidizing acid to the product of step (I) to continue the reaction for 4 hours, and vacuumize to remove the water produced by the reaction until the acid value is ≤ 2.0mgKOH / g, increase the vacuum until the acid value reaches 0.4mgKOH / g, and the hydroxyl value reaches 34mgKOH / g, to obtain DEG polyols modified by oxidized carbon black and terminated with hydroxyl groups, that is, modified DEG polyols;

[0043] (Ⅲ) 500g modified DEG polyol, 100g polyether triol (molecular weight 600), 7.8g (1.3wt%) chain extender 1,3-propanediol, 3.6g (0.6wt%) deionized water, catalyst 0.0282g of bismuth octadecanoate and 0.0318g of catalyst triethylamine (the weight ratio of the two catalysts is 47:53) were mixed with a high-speed mixer at room temperature fo...