DE10022280A1 - Composite material, useful for making e.g. automobile interior components, comprises a polyurethane derived from a specified polyester polyol adhesively bonded to a thermoplastic substrate - Google Patents

Abstract

Composite material comprises a polyurethane (I) adhesively bonded to a thermoplastic substrate. The polyurethane (I) is produced by reacting: (a) an isocyanate-functional prepolymer produced by reacting an isocyanate with a polyester polyol that is the condensation product of adipic acid and/or phthalic anhydride with diols and/or triols; and (b) isocyanate-reactive compounds. Composite material comprises a polyurethane (I) adhesively bonded to a thermoplastic substrate. The polyurethane (I) is produced by reacting a mixture of: (a) an isocyanate-functional prepolymer with an isocyanate group content of 5-48% produced by reacting an isocyanate with a polyester polyol that has a functionality of 2-3 and a hydroxyl number of 40-400 and is the condensation product of adipic acid and/or phthalic anhydride with diols and/or triols of molecular weight 62-3000; (b) isocyanate-reactive compounds; and optionally (c) a catalyst; (d) a propellant; and/or (e) additives. An independent claim is also included for a process for producing the composite material, comprising reacting components (a)-(e) in the presence of the thermoplastic substrate.

Description

The invention relates to composite elements containing

• a) thermoplastic to which adheres
• b) containing the product of the reaction of a reaction mixture
  • a) an isocyanate group-containing prepolymer obtainable from the reaction of at least one isocyanate and a polyester polyalcohol with a functionality of 2 to 3 and a hydroxyl number of 40 to 400 mg KOH / g based on the condensation of adipic acid (ADS) and / or phthalic anhydride (PSA ) with diols and / or triols with a molecular weight of 62 to 3000 g / mol, the prepolymer having an isocyanate group content of 5 to 48%,
  • b) compounds reactive toward isocyanates and, if appropriate
  • c) catalysts,
  • d) blowing agent and / or
  • e) auxiliaries and / or additives
  connects.

Furthermore, the invention relates to processes for the manufacture provision of such composite elements and their use.

Polyisocyanate polyaddition products obtainable by reaction of isocyanates with compounds reactive towards isocyanates, for example polyols, e.g. H. Connections that are at least two Have hydroxyl groups, and composite elements of these Products with other plastics are generally known. A Exposure of these composite elements to high temperatures and Humidity often leads to undesired detachment of plastics from polyisocyanate polyaddition products. Especially when using such composite elements in automotive engineering for which such a burden cannot be excluded, is a replacement of the polyisocyanate polyadducts from the other plastics and thus a destruction of the composite element not acceptable.

In the manufacture of the composite elements and in particular the Polyisocyanate polyaddition products can address the problem show that the starting components, especially the polyol component which is the isocyanate-reactive starting materials  does not result in stable mixtures. Especially with low temperatures, for example below 20 ° C, can individual polyols tend to precipitate out in the polyol component flake or settle in the polyol component. Straight to reproducible production of high quality products it is important to avoid this problem.

The object of the invention was therefore to develop composite elements wrap that due to their excellent mechanical properties can be used for example in automotive engineering and where the adhesion between the plastic and the on it adhering polyisocyanate polyaddition products even at a Storage for 80 hours at 80 ° C and 80% rel. humidity not lost. In particular, the composite elements with. Starting components can be produced, the stable mixtures result and thus be used easily and reproducibly can. It should be especially against isocyanates reactive compounds in the polyol component and / or the iso Do not settle or flocculate the cyanate component.

The task was accomplished through the association described above elements to be solved.

The composite elements according to the invention can be used as thermo plastic plastic (i) usual thermoplastic materials contain, for example polyphenylene oxide (PPO), polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), polymethyl methacrylate (PMMA), acrylonitrile styrene acrylic ester (ASA), poly carbonate (PC), thermoplastic polyurethane (TPU), polyethylene, Polypropylene. The composite elements preferably contain as (i) thermoplastic polyolefin film (TPO) such as polyethylene and / or Polypropylene, polyvinyl chloride (PVC), styrene maleic anhydride (SMA) and / or a polycarbonate / styrene acrylonitrile / acrylonitrile Butadiene blend (PC / ABS).

The plastics (i) can be produced in the form of conventional materials position of the composite elements are used, for example as films, generally with a thickness of 0.2 to 2 mm.

Such films are commercially available, and their fro position is generally known. The foils preferably have one Thickness from 0.2 to 2 mm. At least two can also be used as (i) Layers containing films are used, for example the one layer an ASA and / or polycarbonate material contains.  

The plastics (i) from styrene maleic anhydride (SMA) and / or a polycarbonate / styrene-acrylonitrile / acrylonitrile-butadiene blend (PC / ABS) can be made in the form of common materials the composite elements are used, for example as Ver stiffening part for instrument panels or door side parts.

According to the invention, the plastic (i) adheres Polyisocyanate polyadducts (ii), for example poly urethanes, optionally isocyanurate and / or urea can have structures. The manufacture of this polyiso cyanate polyadducts (ii), preferably the polyurethanes, those in compact or preferably cellular form, for example as soft foam, semi-rigid foam or rigid foam, can particularly preferably be present as semi-rigid foam, takes place according to the invention by the following Implementation.

To achieve better liability between (i) and (ii) especially under humid and warm conditions as well as for position of stable starting components, is essential to the invention Lich characteristic at least one polyester polyalcohol with a Functionality from 2 to 3, preferably 2 and a hydroxyl number from 40 to 400, preferably 40 to 100, particularly preferably 40 to 80 mg KOH / g based on the condensation of adipic acid (ADS) and / or phthalic anhydride (PSA), preferably ADS, with diols and / or triols with a molecular weight of 62 to 3000 g / mol in the form of a prepolymer containing isocyanate groups in the Component (a) for the preparation of the polyisocyanate polyadditions products (ii) used. As a diol and / or triol can for example trimethylolpropane, neopentyl glycol, polytetrahydro furan (PTHF), aliphatic diols with 2 to 12 carbon atoms, e.g. B. ethylene glycol, propane-1,3-diol, pentane-1,5-diol, hexane-1,6- diol, butane-1,4-diol, ether diols and / or ether triols based of ethylene oxide and / or propylene oxide, e.g. B. diethylene glycol, Dipropylene glycol, triethylene glycol, tripropylene glycol, tetra ethylene glycol, tetrapropylene glycol can be used. Prefers the polyester polyalcohol is based on hexane-1,6-diol, butane-1,4- diol and / or monoethylene glycol as the alcohol component.

According to the invention, this polyester polyalcohol is mixed with at least an isocyanate, which is described later as an example are converted to an isocyanate group-containing prepolymer sets, the prepolymer having an isocyanate group content of 5 to 48%, preferably from 20 to 30%. The isocyanate group content has the unit% and is determined according to the standard ASTM D 1638. The isocyanate content of the prepolymer according to the invention  is obtained by methods generally known to the person skilled in the art, for example, by the polyester and the isocyanate in a mass ratio of 0.01: 1 to 0.1: 1. The Implementation can for example at a temperature of 30 to 120 ° C. usually with stirring for a period of 10 to 180 min if appropriate in the presence of known catalysts in well-known containers, equipment or reactors respectively.

The prepolymer containing isocyanate groups according to the invention can for example, be made by placing in a 1 t boiler 900 kg Lupranat® M10R (BASF Aktiengesellschaft) and warmed to approx. 60 ° C and then within approx. 30 minutes 100 kg Lupraphen® 8101 (BASF Aktiengesellschaft) with stirring in 4 portions of 25 kg each. The oil temperature at the mixer boiler is between 75 and 80 ° C. After 30 minutes the Heating turned off and after about 2 hours the reaction is completed. The prepolymer has an NCO content of 28% and Viscosity of 500 mPas at 25 ° C.

Those skilled in the art would expect when using polyesters that the products so produced due to the possibility no improved adhesion for the hydrolysis of the ester bond, especially under damp, especially under warm and damp Would have conditions. Just to solve the task To achieve an improved liability was it for the expert therefore not obvious to use polyester polyols.

A polyester polyol is preferably used containing in (b) a which has a hydroxyl number of 40 to 80 mg KOH / g and a Has functionality of 2 and on the condensation of ADS based on monoethylene glycol and butane-1,4-diol.

The composite elements according to the invention can be produced in such a way that

• a) an isocyanate group-containing prepolymer obtainable from the implementation of at least one isocyanate and one poly ester polyalcohol with a functionality of 2 to 3 and a hydroxyl number of 40 to 400 mg KOH / g based on the Condensation of adipic acid (ADS) and / or phthalic acid anhydride (PSA) with diols and / or triplets with one Molecular weight of 62 to 3000 g / mol, the prepolymer has an isocyanate group content of 5 to 48%,
• b) isocyanate-reactive compounds, and given if
• c) catalysts,  
• d) blowing agent and / or
• e) auxiliaries and / or additives

in the presence of (i).

To produce the products according to the invention, the pre polymer (a) and the compounds reactive toward isocyanates (b) and optionally (d) ge in such amounts for implementation brings that the equivalence ratio of NCO groups from (a) to Sum of the reactive hydrogen atoms of (b) and optionally (d) preferably 0.3 to 1.8: 1, particularly preferably 0.4 to 1.0: 1 and in particular 0.4 to 0.6: 1. If the product (ii) contain at least partially bound isocyanurate groups usually a ratio of NCO groups to the sum of the reak tive hydrogen atoms from 1.5 to 60: 1, preferably 1.5 to 8: 1 applied.

The implementation of the product can be done, for example, by hand casting, by high pressure or low pressure machines, or by RIM-Ver drive (reaction injection molding) usually in open or preferably closed molds are carried out. Suitable processing machines are commercially available (E.g. Elastogran, Isotherm, Hennecke, Kraus Maffei and others).

It has become for the production of compact products as (ii) proven to be advantageous if the components for production of compact polyisocyanate polyadducts before Ver degassing by applying vacuum (1-759 Torr), to get bubble-free molded parts. When processing with Polyurethane (PU) machines, it is also beneficial if during processing the storage container under reduced pressure stand.

The starting components are usually dependent on Application at a temperature of 0 to 100 ° C, preferably from 20 to 80 ° C, mixed and for example in the mold brought in. The mixing can, as already explained, mechanically by means of a stirrer or a stirring screw out, or can be in a conventional high pressure mixing head respectively.

The reaction of the reaction mixture can, for example, in usual, preferably heatable and closable form be performed. Especially in the manufacture of Products that are as smooth as possible are preferred as molding tools used those whose surface is as smooth or defined as possible is ornamented and prefers no bumps, cracks, scratches  or has impurities. The surface of this shape can can be treated, for example, by polishing.

As molds for the manufacture of the products can be customary and commercially available tools are used, the Surface made of steel, aluminum, enamel, teflon, Epoxy resin or other polymeric material, wherein the surface may be chrome-plated, for example hard can be chrome-plated. The molds should be preferred temperable to set the preferred temperatures too can, lockable and preferably to exert pressure be equipped for the product.

The conversion to the polyisocyanate polyaddition products takes place usually at a mold temperature, preferably also one Temperature of the starting components, from 20 to 220 ° C, preferred 30 to 120 ° C, particularly preferably 35 to 80 ° C, for a duration usually 0.5 to 30 min. preferably 1 to 5 min. The Implementation in the mold takes place according to the invention in direct Contact with (i). This can be achieved, for example that (i) before the implementation, if (i) a film is preferably free of wrinkles in the form placed and then the reaction as already described mix on (i) and then preferably the shape closes. Fibers as (e) can both contain in the Reaction mixture can be used, as well as in the form of mats or tissues. If mats or fabrics are used as (e), so can, for example, before filling the reaction mixture into the mold on (i) and then the reaction mixture that does not contain fibers (e) in this process must contain in addition to the mats or fabrics in the Form.

Well-known (cyclo) aliphatic and / or in particular aromatic polyisocyanates, preferred Diisocyanates are used. To manufacture the Invention Composite elements are particularly suitable for aromatic ones Diisocyanates, preferably diphenylmethane diisocyanate (MDI) and tolylene diisocyanate (TDI).

Component (b) can be generally known versus iso cyanate-reactive compounds are used, for example Polyether polyalcohols, polyester polyalcohols and / or poly carbonate diols, preferably polyether polyols and / or polyester polyalcohols, for example those initially mentioned for the preparation of (b) described polyester polyalkhole, usually with a mole eyepiece weight from 500 to 10,000, in particular 1000 to 6000 and  preferably with a functionality over isocyanate groups of 2 to 6. Furthermore, the compounds of the invention (b) in a mixture with chain extension and / or crosslinking means are used. With chain extenders it is predominantly 2-functional alcohols with moles molecular weights from 60 to 499, for example ethylene glycol, Propylene glycol, 1,4-butanediol, 1,5-pentanediol. In the ver wetting agents are compounds with molecular weights from 60 to 499 and 3 or more active H atoms preferably amines and particularly preferably alcohols, for example as glycerin, trimethylolpropane and / or pentaerythritol.

Conventional compounds can be used as catalysts (c) be, for example, the reaction of component (a) with accelerate component (b) strongly. Come into question at for example, tertiary amines generally known for this purpose and / or organic metal compounds, especially tin links. Such catalysts are preferred set to the lowest possible fogging, d. H. to a lowest possible release of volatile compounds from the Implement reaction product (ii), for example potassium acetate and / or Li salts and / or tertiary amines with at least one functional hydroxyl group.

As blowing agents (d) can be used to produce foamed Products (ii), for example soft polyurethane, semi-hard or rigid foams, optionally urea and / or iso Can have cyanurate structures, generally known chemically or physically acting connections are used. As chemical blowing agent can preferably be used water be, which by reaction with the isocyanate groups carbons forms dioxide. Examples of physical blowing agents, e.g. H. those inert compounds, which under the conditions of Evaporating polyurethane formation are, for example, (cyclo) ali phatic hydrocarbons, preferably those with 4 to 8, particularly preferably 4 to 6 and in particular 5 carbon atoms, partially halogenated hydrocarbons or ethers, ketones or Acetates. The amount of blowing agent used depends on the desired density of the foams. The different Blowing agents can be used individually or in any mixtures each other.

The reaction may take place in the presence of (e) Auxiliaries and / or additives, such as. B. fillers, fibers, e.g. B. in the form of fabrics and / or mats, cell regulators, surfaces active compounds and / or stabilizers against oxidatives, thermal or microbial degradation or aging.  

The composite elements according to the invention have the use of the polyester polyols described above, in particular one significantly improved liability between (i) and (ii) on, d. H. a Liability to the thermoplastic carrier material, in particular to PC / ABS and SMA on. This improved liability ensures that at Tear off the foam from the carrier all over foam residues remain on the carrier. According to the invention, the Use of the polyester polyalcohols according to the invention achieved be that the liability between (i) and (ii) when measured according to DIN 53289 or 53530 in new condition and after heat and moisture heat storage reaches a peeling force of ≧ 2.5 N / cm.

The composite elements according to the invention are preferred as construction parts used in vehicle, aircraft or real estate construction for example as dashboards, door panels, hat racks, Consoles, armrests or door mirrors.

By using the polyester polyalcohols in the form of Pre polymers is achieved according to the invention that the polyester poly alcohols are stably integrated in the isocyanate component. On Flocculate or settle the polyester polyalcohols, for example in the polyol component can thus be successfully avoided.

According to the invention, the use of prepolymers is thus obtained Lich from the reaction of at least one isocyanate and one Polyester polyalcohol with a functionality of 2 to 3 and a hydroxyl number of 40 to 400 mg KOH / g based on the Condensation of adipic acid (ADS) and / or phthalic anhydride (PSA) with diols and / or triols with a molecular weight of 62 to 3000 g / mol, the prepolymer having an isocyanate group Contains from 5 to 48%, for the production of stable Polyurethane systems, in particular containing isocyanate components the polyester polyalcohols according to the invention.

Claims (7)

1. Containing composite elements

• a) thermoplastic to which adheres
• b) containing the product of the reaction of a reaction mixture
  • a) an isocyanate group-containing prepolymer is obtained from the reaction of at least one isocyanate and at least one polyester polyalcohol with a functionality of 2 to 3 and a hydroxyl number of 40 to 400 mg KOH / g based on the condensation of adipic acid (ADS) and / or phthalic anhydride (PSA) with diols and / or triols with a molecular weight of 62 to 3000 g / mol, the prepolymer having an isocyanate group content of 5 to 48%,
  • b) compounds reactive toward isocyanates and, if appropriate
  • c) catalysts,
  • d) blowing agent and / or
  • e) auxiliaries and / or additives
  connects.

2. Composite elements according to claim 1 containing as thermo plastic plastic polyethylene, polypropylene (TPO), Styrene maleic anhydride (SMA), polyvinyl chloride (PVC), Polyphenylene oxide blends (PPO) and / or a polycarbonate / Styrene-acrylonitrile / acrylonitrile-butadiene blend. 3. Composite elements according to claim 1, characterized in that the polyester polyol for the preparation of the reaction product (a) a hydroxyl number of 40 to 100 mg KOH / g and one Has functionality of 2 and on the condensation of Adipic acid (ADS) with hexane-1,6-diol, butane-1,4-diol and / or Monoethylene glycol based.   4. A process for the production of composite elements containing (i) thermoplastic and adhering to it polyisocyanate polyaddition products, characterized in that

• a) an isocyanate group-containing prepolymer obtainable from the reaction of at least one isocyanate and at least one polyester polyalcohol with a functionality of 2 to 3 and a hydroxyl number of 40 to 400 mg KOH / g based on the condensation of adipic acid (ADS) and / or Phthalic anhydride (PSA) with diols and / or triols with a molecular weight of 62 to 3000 g / mol, the prepolymer having an isocyanate group content of 5 to 48%,
• b) compounds reactive toward isocyanates, and optionally
• c) catalysts,
• d) blowing agent and / or
• e) auxiliaries and / or additives

in the presence of (i). 5. The method according to claim 4, characterized in that one as (i) polyethylene, polypropylene (TPO), styrene maleic acid anhydride (SMA), polyvinyl chloride (PVC), polyphenylene oxide Blends (PPO) and / or a polycarbonate / styrene-acrylonitrile / Acrylonitrile-butadiene blend is used. 6. The method according to claim 4, characterized in that a Polyester polyol containing in (b) a hydroxyl number of 40 to 100 mg KOH / g and a functionality of 2 indicates and on the condensation of adipic acid (ADS) with Hexane-1,6-diol, butane-1,4-diol and / or monoethylene glycol based. 7. Use of prepolymers available from the reaction at least one isocyanate and at least one polyester polyalcohol with a functionality of 2 to 3 and one Hydroxyl number from 40 to 400 mg KOH / g based on the Condensation of adipic acid (ADS) and / or phthalic acid hydride (PSA) with diols and / or triols with one molecular weight from 62 to 3000 g / mol, the prepolymer having a Has isocyanate group content of 5 to 48% provision of stable polyurethane systems.