Method of producing soft to semi-rigid polyurethane integral foamed plastics

FIELD: polymer production.

SUBSTANCE: invention relates to foamed polyurethane molded products with thickened edge zone with simplified density and clearly expressed more soft cellular core. Soft to semi-rigid polyurethane integral foamed plastics are prepared by interaction of (i) organic and/or modified organic polyisocyanates or their polymeric precursors with (ii) at least one polyol component with hydroxyl number 20 to 200 and functionality 2 to 6, if necessary in combination with (iii) at least one polyol component with hydroxyl number 201 to 899 and functionality 2 to 3, and also (iv) at least one component functioning as chain extension and having hydroxyl number or amine number 600 to 1850 and functionality 2 to 4 in amount 3 to 20% based on the summary weight of (ii) and (iii), and, if necessary, (v) known additives, activators, and/or stabilizers in presence of 0.05-0.6% water (based on summary weight of (ii) and (iii)) and mixtures of pore agents containing 1,1,1,3,3-pentafluorobutane and at least one other fluoroalkane in amount 0.2-10% of the summary weight of components (ii)-(v). Thus obtained foamed plastics with integral structure are characterized by Shore hardness of edge zone 30 to 90, rigidity in compression deformation 30 and 350 kPa, and apparent density 150 to 900 kg/m³.

EFFECT: increased assortment of foamed plastics.

7 cl, 1 tbl, 9 ex

The object of the invention is a method of obtaining from soft to semi-rigid polyurethane molded products with a compacted edge zone with a given stiffness and clearly expressed softer cellular core, the so-called integral foams, in which as a physical blowing agent used is not combustible mixture of Tarakanov containing 1,1,1,3,3-pentafluorobutane (R 365mfc).

Before they were installed ozone-depleting properties monitorability (R 11), it almost exclusively used as a blowing agent to create a compacted edge zone with a cellular internal structure of soft to semi-rigid polyurethane moulded products. After the ozone-depleting properties of chlorinated hydrocarbons became known, there have been many attempts to use other types of pore-formers for the production of cellular polyurethanes.

Thus, in European patent application EP-A 364854 describes a method of obtaining a molded product with a compacted edge zone and a cellular core, mainly Shoe soles, from known starting compounds, but using a low-boiling aliphatic and/or cycloaliphatic hydrocarbons with 4 to 8 carbon atoms in the molecule. The disadvantage of this gaseous blowing agent, however, is its Flammability.

From the European patent application EP-A 381986 know the use of Tarakanov with 3-5 carbon atoms as a blowing agent upon receipt of polyurethane foams. In U.S. patent US-A 5906999 described receiving a flexible integral foams using 1,1,1,3,3-pentafluoropropane (R 245fa). But it is noted that upon receipt of integral foams with these pore-get foam with unsatisfactory integral structure.

The objective of the invention is the development of a method of producing a flexible integral foams with an explicit integral structure, which is equivalent to the structure of products, foamed using ftorhlorbromuglerodami (FCKW) or galogenirovannyie of ftorhlorbromuglerodami (HFCKW).

It was found that by using certain mixtures of fluorocarbons as pore-forming substance can be obtained integral foams, equivalent in terms of stiffness in compression and surface hardness systems, foamed through R 11 or R 141b, and hydrocarbon foaming systems. Moreover, these compounds are non-flammable, which means a great advantage in the manipulation and processing.

Therefore, an object of the present invention is a method of obtaining from soft to semi-rigid polyurethane molded products with a compacted edge zone and a soft honeycomb core, which is subjected to interaction

a) organic and/or modified organic polyisocyanate and/or formal is OLIMAR MDI

b) at least one polyol as one component with a hydroxyl number (OH-number of from 20 to 200 and a functionality of from 2 to 6, preferably from 2 to 3,

C) if necessary, in combination with a polyol as one component with a hydroxyl number (OH-number) from 201 to 899 and functionality from 2 to 3, and with

g) at least one component, which is the extension chain with a hydroxyl or amine number of from 600 to 1850 and functionality from 2 to 4 and

d) if necessary, known additives, activators and/or stabilizers

in the presence of water and mixtures of pore-containing 1,1,1,3,3-pentafluorobutane and at least one other floralcy.

Preferably use 1,1,1,3,3-pentafluorobutane (R 365mfc) in a mixture of 1,1,1,2-Tetrafluoroethane (R 134a) or 1,1,1,3,3-pentafluoropropane (R 245fa). For the method according to the invention preferably do not use combustible pore. Especially preferred, for example, a mixture of 90 to 95 mol%. R 365mfc with 5-10 mol%. R 134a. In another preferred variant of the method according to the invention using a mixture of 40-95 mol%, preferably from 40 to 60 mol%. and especially from 45-55 mol%. R 365mfc with 5-60 mol%, preferably 40-60 mol%. and especially with 45-55 mol%. R 245fa.

As previously mentioned, in the method according to the invention as blowing agent is additionally used water. The amount of water additionally, the led in the polyurethane composition, is usually from 0.05 to 0.6 mass parts, mainly from 0.1 to 0.4 mass parts per 100 mass parts component (b) and (C) (polyol as one of the components). The number of mixtures of fluorocarbons is from 0.2 to 10 mass parts, preferably from 0.5 to 8 mass parts per 100 mass parts of component b), C), d) and e), or b) and d)or b), C) and d), or (b), d) and e) depending on the specific composition of the obtained product interaction.

As for the organic polyisocyanates (a), then we are talking about the known aliphatic, cycloaliphatic, alifaticheskih and predominantly aromatic polyhydric isocyanates, such as, for example, cited in European patent application EP-A 364854. Especially suitable toluylenediisocyanate and diphenylmethanediisocyanate, products, modifications, or their respective prepolymers, which can be modified urethane groups, urea groups, birmana, allophanate, carbodiimide or uretdione. As aromatic polyisocyanates preferably include: 4,4-diphenylmethanediisocyanate, mixtures of 2,4'- and/or 4,4'-diphenylmethanediisocyanate or crude 4,4'-methylene-bis(phenylisocyanate) and/or 2,4 - and/or 2,6-toluylene-diisocyanate and their mixtures with each other.

As a polyol as one component b) is suitable polyol as one of the components with a hydroxyl number of from 20 d is 200, preferably from 20 to 50, and a functionality of from 2 to 6, mostly from 2 to 3, and the corresponding polyether polyols based on polyethers have srednecenovogo molecular weight of from 2000 to 8000, and the corresponding polyether polyols based on polyesters have srednecenovogo molecular weight of from 2000 to 4000. If necessary, as a polyol as one component) can be shared polyols with a hydroxyl number from 201 to 899 and functionality from 2 to 3. Particularly suitable polyols are selected from the group of polyether polyols based on esters and ethers, such as obtained by the reaction of the accession of alkalisation, such as ethylene oxide and propylene oxide, to a multifunction source connection, such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, sorbitol and/or Ethylenediamine, or obtained by condensation of dicarboxylic acids such as adipic acid, succinic acid, glutaric acid, cork acid, sabotinova acid, maleic acid, phthalic acid, predominantly, with bifunctional hydroxyamphetamine, such as ethylene glycol, propylene glycol derived from ethylene oxide and oxide propylene, as well as glycerol, trimethylolpropane, Ethylenediamine, propylene glycol, ethylene glycol, sorbitol and a mixture of the starting compound. Can also as a polyol as one component b) used modified polyols, such as obtained grafted copolymerization of polyols with styrene and/or Acrylonitrile, in the form of dispersions of polyureas or PIPA polyols (polyols obtained by polyprionidae polyisocyanates). The polyether polyols based on esters and ethers can be used both individually and in mixtures with each other.

As component d) is particularly suitable extender chain, hydroxyl number or amine number ranging from 600 to 1850, and a functionality of from 2 to 4, especially from 2 to 3. As examples, glycols such as ethylene glycol, 1,4-butanediol, glycerin, trimethylolpropane and short-chain products of their oxyalkylene, as well as the isomers of diethyltoluenediamine. Cross-linking component g) (component, which chain extension) is used in an amount of from 3 to 20% wt. relative to the sum of the amounts of polyol as one of components b) and C) (if present), and as preferred diols ethylene glycol and 1,4-butanediol, and the diamine isomers of diethyltoluenediamine.

As component d) can be used, in principle, well-known specialist additives, activators and/or stabilizers. They may, for example, compounds containing tertiary and is kinogruppy, such as 1,4-diazo-[2.2.2]-bicicletta or bis(2-dimethylaminoethyl) ether, ORGANOMETALLIC compounds such as dilauryl dimethylurea or dilaurate dibutylamine, paste dyes, means of protection from yellowing, fillers, flame retardants, inert lubricants or stabilizers, such as described in European patent application EP-A 364854.

Their number depends on the specific purpose and can be determined by experiment.

Obtaining a molded product according to the invention are also known to the expert and does not require more detailed description (see European patent application EP-A 364854).

Obtained by the method according to the invention from soft to semi-rigid polyurethane foam with an integral structure, as a rule, have in the marginal zone of the shore a hardness between 30 and 90 and stiffness with deformation between 30 and 350 kPa at an apparent density between 150 and 900 kg/m³.

Particularly advantageous in obtained by the process according to the invention of integral foams combination of high surface hardness (shore A) with low stiffness with deformation of the compression molded product, which indicates that an explicit integral structure.

The use of molded articles according to the invention are, for example, a Bicycle seat, safety valve, the interior of the premises ABT the mobiles (armrests, the head, covering the steering wheel), motorcycle seats, armrests for office furniture, as well as procedural chairs in medicine.

Examples

Description raw material

The polyols

Polyol 1: polyetherpolyols with a hydroxyl number of 29 with predominantly primary hydroxyl groups obtained by the reaction of accession to 80% wt. of propylene oxide and 20% wt. of ethylene oxide to propylene glycol as the source connection.

Polyol 2: polyetherpolyols with a hydroxyl number of 28, with a predominance of primary hydroxyl groups obtained by the reaction of accession to 80% wt. of propylene oxide and 20% wt. of ethylene oxide to trimethylolpropane as the parent compound, which is grafted stimulational in the amount of 20% wt.

Polyol 3: polyetherpolyols with a hydroxyl number of 35, with a predominance of primary hydroxyl groups obtained by the reaction of accession 87% wt. of propylene oxide and 13% wt. of ethylene oxide to trimethylolpropane as the source connection.

The polyisocyanate

The MDI prepolymer with an isocyanate content of 28 wt.%, obtained by the interaction of a mixture of polyisocyanates number difenilmetana received by postironium condensation products of aniline and formaldehyde and containing 30% wt. isocyanate with 80% wt. diisocyanatobutane, and 20% wt. more Vysokoe hernych homologues, with the polyester having a hydroxyl number of 500 obtained by the reactions of addition of propylene oxide to propylene glycol as the source connection.

The pore-forming

Obtaining a test sample

The following mixture of raw material is loaded into heated to 40°With plate form for mechanical processing of polyurethanes in the usual way with dimensions of 190×155×20 mm, compacted up to 250 kg/m³and remove from the mold after 10 minutes. The temperature of the source of the raw mix is 25°C.

Polyol as one composition by mass:

(SH 205, Witco Surfactants GmbH, D-36396 Steinau)

(DABCO® 33LV, Air Products GmbH, D-45527 Hattingen).

Recipe sample for testing

The profile of properties of integral foams is determined by specific criteria by surface hardness (measured on the shore a), and by the stiffness in compression. Best is of the highest possible surface hardness (high apparent density in the outer region), combined with low stiffness in compression in comparison with envisaged for the total apparent density. The dimensions for the evaluation of the integral structure can take the ratio of the integral structure - correction factor of stiffness in compression and surface hardness. The smaller the value of the correction coefficient, the better the integral structure.

As examples, this ratio strongly depends on the choice of blowing agent. Achieved with a mixture of pore-formers according to the invention correction factors (examples 4-6) is significantly lower than when using R 134a, R 245fa or R 356mffm and alkanolamine systems. Furthermore, a pore-forming mixture is not flammable in contrast alkanal or pure R 365mfc.

1. The method of obtaining from soft to semi-rigid polyurethane products with compacted edge zone and a soft honeycomb core, which is subjected to interaction

a) organic and/or modified organic polyisocyanates and/or calimari polyisocyanates with,

b) at least one polyol as one component with a hydroxyl number of from 20 to 200 and a functionality of from 2 to 6,

C) if necessary, in combination with a polyol as one component with a hydroxyl number from 201 to 899 and functionality from 2 to 3, and

g) at least one component, which is the extension chain with a hydroxyl number or amine number of from 600 to 1850 and functionality from 2 to 4 in an amount of 3-20 wt.% relative to the sum of the amounts of components b) and C), and

d) if necessary, known additives, activators and/or stabilizers

in the presence of water in amount of from 0.05 to 0.6 wt.% relative to the sum of the amounts of components b) and C) and mixtures of pore-containing 1,1,1,3,3-pentafluorobutane and at least one other floralcy, in the amount of from 0.2-10 wt.% relative to the sum of the amounts of components b)-d).

2. The method according to claim 1, wherein a mixture of pore contains 1,1,1,2-Tetra-foraten.

3. The method according to claim 2, in which the content of 1,1,1,2-Tetrafluoroethane in a mixture of pore ranges from 5 to 10 mol.%.

4. The method according to claim 1, wherein a mixture of pore contains 1,1,1,3,3-pentafluoropropane.

5. The method according to claim 4, in which the content of 1,1,1,3,3-pentafluoropropane in a mixture of pore ranges from 5 to 60 mol.%.

6. The method according to one of claims 1 to 5, in which as to the component d) is used glycols.

7. The method according to one of claims 1 to 6, in which component d) use the isomers diethyltoluenediamine.