RU2252234C2 - Polyol composition for polyurethane production - Google Patents

Abstract

FIELD: organic chemistry, in particular polyol composition for cold-cured polyurethane production.

SUBSTANCE: claimed composition contains (pts mass): polyethertriol or mixture of polyethertriol with molecular weight of 4500-6500 and average hydroxyl functionality of 3 - 100; ethylene glycol - 3.5-6.2; 1-4-butandiol - 3,5-8,0; triethylene diamine - 0.53-0.65; water - 0.25-0.50; organosilicate foam regulator - 0.002-0.004; and high boiling by-product from isoprene production based on alkyl- and oxyalkyl-substituted dioxacyclanes (e.g., 1,3-dioxane containing 1-4 mass % of hydroxyl groups) as organic filler - 2-100. Said filler may be used in mixture with oil plasticizer. Polyurethane obtained according to present method has Shore A hardness of 20-50, and is useful in automobile industry, and as material for gasket and sealing.

EFFECT: composition for production of polyurethane with increased hardness.

2 cl, 1 tbl, 3 ex

Description

The present invention relates to a composition of a polyol as one composition suitable for producing cold formed polyurethane and can be used for the manufacture of technical products with a hardness of from 20 to 50 units. by Shore A.

Polyurethane elastomers are effectively used in the furniture industry, automotive, construction, insulation and packaging, in the shoe industry, etc.

Each application presents corresponding requirements for the compositions of the components of the polyurethane composition. The polyol component, as a rule, is a physical mixture, which includes several types of oligoesters, polymer extenders and crosslinkers, catalysts, surfactants, modifiers and other excipients known in the chemistry of polyurethanes (Oligoesters. Isocyanates. Systems. - Catalog. - NIITEKHIM. 1987, p. 18, 23).

To reduce the polymer consumption and (or) cheaper polymers, including polyurethanes, fillers are introduced into them.

As fillers, natural (chalk, limestone, marble) and synthetic (precipitated) calcium carbonates, magnesium silicate (talc), barium sulfate (heavy spar), aluminum hydrosilicate (kaolin), aluminum trihydroxide, mica, sand, and fillers of plant origin are used ( wood flour, ground nutshell, sawdust), industrial and household waste (polymers, polystyrene, natural and synthetic fiber, tow, shredded trimmings of tires and carpets, lignosulfonates, paper waste paper) (Tarakanov O.G. Shamov I.V., Alpe pH VD Filled foams. M: Chemistry, 1989. P.78-82).

The principal disadvantage of polyol as one compositions using the above fillers is that they form a suspension in the component to which they are added. To prevent sedimentation of the filler, consumables must be equipped with agitators and recirculation systems. It is also necessary to use special pumps suitable for pumping slurries. In addition, the filler is always, to one degree or another, incompatible with the polymer phase, changes the foaming parameters and, as a consequence, the macrostructure of the final polymer material. It is known that the structure of filled polyurethane depends on many characteristics of the filler and, above all, on its content and homogeneous distribution in the polymer matrix. In order to homogeneously mix the filler with the polyol, you need to either treat it with an appropriate sizing, or increase the content of surfactants in the polyol composition, or take a polyol with a higher content of hydroxyethyl units, or use a special mixer.

All these measures lead to excessive laboriousness of the process, complicating its hardware design and increasing the cost of the final polymer product.

To improve the stiffness of block and molded polyurethane foams, stable dispersions of polymers in polyether — polymer polyols — are used. Preferred polymers are polystyrene and copolymers of styrene with acrylonitrile. Dispersed solid phase particles can be considered as fillers like conventional inorganic fillers such as CaCO ₃ (Gier DRO Nell, MRAdams et al. Fillers, Hard Phases and Copolymer Polyols-their. Different Mechanism to Reinforce Flexibe Polyurethane Foams / Polyurethanes Expo 98, September 17-20 . 1998, p. 227-236).

For example, a polyol composition for producing flexible polyurethane foam is known, including a simple Laprol 5003-2B-10 polyether triol containing more than 75% primary hydroxyl groups, a foam stabilizer, a catalyst, a blowing agent, a primary diamine, an oxyalkylated ethylenediamine (Lapramol) and a dispersion of acrylonitrile copolymerization product and styrene in a medium of polyether triol, which is a white liquid product with a viscosity of 1800-12400 MPa with a hydroxyl number of 26-30 mg KOH / g and a filler content of 20 wt.% (Auth. St. USSR No. 1495341, publ. 07.23.1989). The dispersion is obtained by copolymerization of equal mass amounts of these monomers at 100 ° C, followed by distillation of the volatiles. The proposed polyol as one composition when mixed with an isocyanate component can reduce the density, increase the elastic properties of the manufactured parts.

The disadvantage of this composition is its high viscosity. As a result of this, there is a decrease in the fluidity of the reaction mass, which causes difficulties in obtaining products from polyurethane foams and adversely affects the properties of foams. Polyol compositions are known for producing latex-like elastic polyurethane foams, which are obtained by reacting two different polyols with an isocyanate component in the presence of a catalyst, crosslinking and foaming agents, and a foam stabilizer. The polyols used are: a major amount of a polymer polyol containing a basic polyol having a molecular weight ranging from 2500 to 6500, an average nominal functionality of at least 2.0, a primary hydroxyl content of at least 40% and a polymer stably dispersed therein; the minimum amount of hydrophilic polyol having a molecular weight of from 2000 to 5500, an ethylene oxide content of at least 40 wt.% and a primary hydroxyl content of at least 50% (RF patent No. 2166516, publ. 10.05.2001).

The resulting flexible polyurethane foams have good elasticity, but the formulation used is complicated and expensive.

Closest to the technical nature of the proposed formulation of the polyol as one composition is a polyol as one composition for producing cellular polyurethane molded products with a compact surface, consisting of at least one simple polyether polyol with a molecular weight of 2000-10000 and / or at least one complex polyester polyol with a molecular weight of 2000 -10000, at least one compound, with a molecular weight of 62-199.9, taken in an amount of 2-15% of the weight of iolnogo component, a blowing agent and other auxiliaries known in polyurethane chemistry, which are used as polyols: polyether diols having a molecular weight of 4000 and an ethylene oxide content of 30%; polyether triol having a molecular weight of 6200 and an ethylene oxide content of 20%; polyether triol having a molecular weight of 4800 and an ethylene oxide content of 15%; polyether triol grafted in an amount of 20% of the total weight of a mixture of styrene and acrylonitrile (in a weight ratio of 40:60) and an ethylene oxide content of 15%; the molecular weight of the grafted polyester is 6000, and in which ethylene glycol, 1,4-butanediol or mixtures of such simple diols are used as difunctional compounds for the isocyanate polyaddition reaction; carbamates and water are used as a blowing agent (RF patent No. 2138523, publ. 09/27/1999 - prototype).

Get foams with properties - density: 200-700 kg / m ³ , shore hardness A: 20-70.

Common disadvantages of styrene-acrylonitrile mixtures as preferred monomers for producing polymer polyols are:

- increased viscosity, limiting the concentration limits of the use of polymer-polyol;

- the tendency to form agglomerates, leading to problems during storage and processing;

- deterioration of the color of the foams due to the formation of cyclic polymers;

- smell.

The use of monomer mixtures enriched with styrene in the composition of the polyol as one composition of RF patent No. 2166516 gives dispersions with lower viscosity, color, and odor.

In the synthesis of concentrated dispersions (with a solids content of 35-43%), it is necessary to ensure an acceptable polymer-polyol viscosity, its high stability, the minimum size of suspended particles and the absence of their agglomeration.

The polymer dispersions indicated in the above patents, in comparison with many other fillers, are less abrasive, but prone to sticking. But their main drawback is the high cost, comparable to the cost of polyurethane. This makes, in most cases, the use of polymer dispersions as fillers not very effective.

The disadvantages of filled polyol as one compositions can be minimized when the filler is combined with the liquid oligomeric composition, i.e. the filler should form a homogeneous system (solution) with the component into which it is introduced. In this case, the amount of filler is limited only by the quality of the structure of the filled polyurethane. It is also desirable that the filler does not stand out in a separate phase when mixing the components of the polyurethane composition, as well as in the resulting polymer. In this case, the introduction of the filler should not create difficulties in the manufacture of products or impair their performance.

The present invention is to develop a composition filled polyol as one composition suitable for producing polyurethane cold forming, eliminating the above disadvantages.

The solution to this problem is achieved using a polyol as one composition containing a simple polyether triol or a mixture of simple polyether triols with a molecular weight of 4500-6500 and an average hydroxyl functionality of 3, a chain extender, a catalyst, a blowing agent, an organosilicon foam regulator, an organic filler. As a last resort, the polyol composition contains a high boiling point by-product of the production of isoprene based on alkyl and hydroxyalkyl substituted 1,3-dioxanes with a mass fraction of hydroxyl groups of 1-4% or a mixture thereof with an oil plasticizer.

In accordance with the invention, compounds of the trademark Laprol 5003-2B-10, 5003-2-15, Laprol 6003-2B-18 or mixtures thereof are used as polyether triols; are ethoxylated polyoxypropylene triols with a molecular weight of 4500-6500 obtained by anionic polymerization of propylene and ethylene oxides using glycerol as a starting compound. Available in accordance with TU 226-006-10488057-94 and TU 2226-020-1-488057-94.

Ethylene glycol, 1,4-butanediol or mixtures of such simple diols are used as a chain extender.

As a catalyst for the reaction of urethane formation, triethylenediamine is used and, if necessary, in a mixture with an organotin compound (tin octoatom or dibutyltin dilaurate).

Foaming is carried out due to carbon dioxide released during the interaction of the polyisocyanate with water.

Stabilization of the cellular structure during foaming is achieved using the well-known silicone block copolymer - Penta (brand), manufactured according to TU 2257-008-40243042-99.

A high-boiling by-product of the production of isoprene from formaldehyde and isobutylene is used as an organic filler (Rakhmankulov D.L., Karakhanov R.A., Zlotsky S.S. et al. Chemistry and technology of 1,3-dioxacyclanes. Results of science and technology. Technology organic substances, vol. 5, M .: VINITI, 1979, 288 p.). The high-boiling by-product is a mixture of various alkyl- and hydroxyalkyl-substituted 1,3-dioxanes with a mass fraction of hydroxyl groups of 1-4% (Ogorodnikov S.K., Idlis G.S. Isoprene production. L .: Chemistry, 1973, 296 s. .). The specified product is a transparent yellow oily liquid and has the following physicochemical properties:

Density at 20 ° С, g / cm ³ 1,02-1,09

Essential number, mg KOH / g 1.5-4.0

Mass fraction of hydroxyl groups,%, in the range 1-4

Flash point in an open crucible, ° С, not lower than 130

Pour point, ° C, not higher than minus 40

As a plasticizer of petroleum origin, petroleum oil is used, selected from the group of domestic oils, including stabiloplast-62, staboil-18, netoxol, naphthoplast, vaseline oil I-8A. Petroleum oils are produced by industry:

stabiloplast-62 according to TU 38.101545 - 80

stable-18 according to TU 38. 101367 - 78

netoxol according to TU 38. 101999 - 84

naphthoplast according to TU 38 101 936 - 83

I-8A vaseline oil in accordance with GOST 20799 - 88

The proposed polyol as one composition for producing cold molded polyurethane preferably includes the listed components in the following ratio in the composition, parts by weight:

polyether triol or a mixture of polyether triols - 100;

ethylene glycol - 3.5-6.2;

1,4-butanediol - 3.5-8;

triethylene diamine - 0.53-065;

water 0.25-0.5;

organosilicon foam regulator - 0.002-0.004;

organic filler or mixtures thereof with petroleum

plasticizer - 2-100.

The composition is prepared in a known manner by mixing the components. Polyether triol or a mixture of polyether triols, an organosilicon foam regulator, a chain extender, a catalyst, a blowing agent are combined and the resulting mixture is mixed with an organic filler. The resulting polyol as one composition is stable during storage (at least 8 weeks). During this period of time, the composition does not exfoliate and does not lose its activity with respect to the isocyanate component.

An essential distinguishing feature of the proposed formulation of the polyol as one composition is the use of a high-boiling by-product of the production of isoprene based on alkyl and hydroxyalkyl substituted 1,3-dioxanes with a mass fraction of hydroxyl groups of 1-4% or its mixture with an oil plasticizer as an organic filler. The amount of filler in the composition: up to 100 wt.h. per 100 parts by weight polyether triol. As a plasticizer use petroleum oil.

The industrial applicability of the proposed polyol as one composition is confirmed during the pilot industrial production of products based on it using an industrial low-pressure machine and unheated forms.

Processing conditions:

- the mass ratio of components during processing, depending on the requirements for stiffness of the resulting foam can vary from 2.5 to 3.2;

- the temperature of the reagents (polyol as one component and polyisocyanate component) is 18-23 ° C;

- stay in shape - 3 minutes;

- fluidity is good.

Technological characteristics of the foam obtained by the method of free foaming in accordance with TU 6-55-32-89 (Polyurethane systems. Technological test method):

- start time - (15 ... 2) s;

- foam rising time - (35 ... 45) s.

Styrofoam Properties:

- apparent density, kg / m ³ 350-400

- shore hardness A (unit scale) 20-50

- tensile strength, n / cm ² 60-90

- relative elongation,% 150-220

To assess the physical and mechanical readings of the finished products, the following regulatory documents were used: GOST 409-77 (volumetric weight of the foam), GOST 15873-70 (elongation at break).

The compositions of the polyol as one compositions are shown in the table.

The introduction of a high-boiling by-product of the production of isoprene based on alkyl- and hydroxyalkyl-substituted 1,3-dioxanes with a mass fraction of hydroxyl groups of 1-4% in various proportions with commonly used simple polyether triols into the formulation of the polyol component of the product provides the following advantages: the preparation of the polyol composition is simplified; the manufacturability of processed compositions is increased; convenience and safety in work due to low pour point and high flash point; the possibility of introducing in relatively large quantities due to compatibility with simple polyether triols, including with water; the number of polyether triols used is reduced; increases the rigidity of the foam.

In addition, since the cost of the by-product of the production of isoprene and petroleum plasticizer is less than the cost of simple polyether triol, their partial replacement with polyether triol leads to a cheaper formulation while maintaining all quality indicators of the molded products.

Thus, the proposed polyol as one composition suitable for producing polyurethane cold forming, which in terms of performance can be used in various industries, in particular automotive, as gaskets, seals.

Table Polyol formulations Components Content 1 2 3 Laprol 5003-2B-10 87 - - Laprol 5003-2-15 - 98 100 Laprol 6003-2B-18 thirteen 2 - Ethylene glycol 3,5 6.2 6 1,4-butanediol 5 3,5 8 Triethylenediamine 0.53 0.63 0.65 Water 0.25 0.4 0.5 Silicone Foam Regulator - 0.002 0.004 Organic filler or mixtures thereof with oil plasticizer 2 48 100

Claims (2)

1. Polyol as one composition for producing cold formed polyurethane, comprising a simple polyether triol or a mixture of simple polyether triols with a molecular weight of 4500-6500 and an average hydroxyl functionality of 3, ethylene glycol, 1,4-butanediol, triethyl diamine, water, an organosilicon foam regulator and an organic filler, characterized in that that as an organic filler, it contains a high boiling point by-product of the production of isoprene based on alkyl and hydroxyalkyl substituted dioxacyclanes with a mass fraction of hydroxyl g rup 1-4% or its mixture with an oil plasticizer, in the following ratio of components, parts by weight: polyether triol, or a mixture polyether triols 100 ethylene glycol 3.5-6.2 1,4-butanediol 3.5-8.0 triethylenediamine 0.53-0.65 water 0.25-0.50 organosilicon foam regulator 0.002-0.004 organic filler or its mixtures with oil plasticizer 2-100 2. The polyol as one composition according to claim 1, characterized in that it contains petroleum oil selected from the group consisting of stabiloplast, 62, stabiloil 18, netoxol, naphthoplast, I-8A petrolatum as an oil plasticizer.