CS203369B1 - Reactive mixture making reach a wide variability of polymere material - Google Patents

Description

It is an object of the present invention to provide a reactive mixture which allows a wide range of properties of the resulting polymer mass to be obtained by additionally applying heat to the reactive mixture. It is suitable especially for application and casting.

Polyurethane polymers, due to their very good physico-mechanical and hygienic properties, are finding an increasingly widespread use in industry. Particularly important is the production of paints and coatings, casting systems. Significant successes have been achieved in the production of deposition and bonded formations, plastic skins for clothing, footwear, upholstery, haberdashery, in the production of rigid to very soft and flexible laminates and self-supporting foils.

Reactive polyurethane systems are increasingly penetrating this field of application. Their particular advantage is the rapid, operative process of preparing the reaction mixture, which is usually immediately followed by the actual application process, e.g. deposition. Modification of the properties of the resulting product can be achieved by the addition of auxiliary components such as filler activators, surfactants etc. It is particularly advantageous to use systems which do not contain organic solvents in their assembly, the presence of which is associated with deterioration of working environment solvents. In this regard, reactive systems comprising a reactive isocyanate component have a significant position, which, when reacted with an amine or polyamide component, yields linear, branched or crosslinked products with a wide range of properties. The disadvantage of this system is the limited reaction life of the mixture due to the high reaction rate. Typically, special types of substituted amines are used as extending agents to suppress this to some degree adverse effect. However, this limits the range of properties of the resulting products, but it is also to be understood that the reaction of the isocyanate and amine groups occurs immediately after mixing the components. when the final state is slowed down.

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These drawbacks are largely eliminated by the reactive mixture, allowing a wide variability in the properties of the resulting polymer mass, formed by the additional heat treatment of the reactive mixture, which contains as one of the basic components a reactive prepolymer which is a polyol addition polymer, especially polyether or polyester with polyisocyanate. aromatic, aliphatic, cycloaliphatic, or mixtures thereof, wherein the chains of this addition product have a reactive isocyanate ending according to the invention, characterized in that it comprises a polymeric modification component which is polyvinyl chloride in an amount of 1 to 50% by weight. and a blocked polyamine extender which is an adduct of polyamine, optionally of a polyainainamide of an aliphatic or cycloaliphatic nature, or a mixture thereof with carbon dioxide,

The composition according to the invention enables a wide variation in the processing properties of the solvent-free composition as well as the properties of the resulting polymer mass produced by the additional effect of heat on the reactive composition.

The effect of heat, in particular at a temperature of 120 to 180 [deg.] C., decomposes the addition product of the polyarain extender and carbon dioxide, and reacts the present isocyanate groups of the reactive prepolymers with the released amine groups. The origin of this reaction can thus be selected.

The composition of the present invention is characterized in that it comprises a polymeric modifying component, which is polyvinyl chloride, in an amount of 1 to 50% by weight. As has been found, the course of the curing reaction can be controlled not only by the ratio of the reactants, prepolymers and extenders, but also by the addition of polyvinyl chloride and the other modifiers mentioned below. Depending on the amount added, this polymer acts as a dispersion medium of the mixture. Furthermore, it has been found that in the selection of certain types of polyvinyl chlorides, polyvinyl chloride is also a chemically active ingredient to isocyanate groups, so that, at normal storage temperatures, it can achieve increased viscosity of those compositions, e.g. low fillers, which are too viscous. Polyvinyl chloride is also reactive to the polyamine component under thermal curing conditions, although these processes are complex and incomplete, yet the reaction with polyamines always goes to a certain time-dependent degree.

In addition, however, in the resulting polymer system, the polyvinyl chloride affects the plastic properties of the deformation content, the thermoformability, the high frequency sensitivity, etc.

The reactive mixture according to the invention may contain 0.1 to 20% by weight. plasticizers or mixtures of plasticizers based on aromatic, aliphatic or inorganic dicarboxylic acid esters, such as, for example, phthalic, adipic, sebacic, phosphoric, or glycol derivatives, citric acid, ricinoleic acid, diphenyl derivatives, or a mixture thereof. In addition to the components mentioned, it may contain 0 to 20% by weight. a polyol, especially a polyester or polyethers, a diol, or a triol, or derivatives or mixtures thereof, wherein the polyol contains reactive hydroxyl groups. The addition of said compounds can deliberately regulate chain branching, the frequency of urethane bonds per chain length, and hence the rigidity or elasticity of the resulting polymer, hydrophilic properties, and the like.

The ratio of polyisocyanates to polyols in prepolymers may be different from stoichiometric, either for reasons of viscosity control, the final blend composition, or for the purpose of adjusting the reaction ratios when curing the blend, which also has a secondary effect on the formation of physico-mechanical properties. Excess isocyanates, especially low volatility, can lead to the formation of stiffer, stiffened structures during curing. In any case, the reactive prepolymer has an isocyanate ending which reacts upon thermal decomposition of the blocked polyamine extender with primary or secondary, optionally amide or imide groups. At the same time, carbon dioxide is released, which can act as a blowing agent under certain conditions. If very thin layers, e.g. about 0.1 mm, are applied from the reactive mixture, a lightweight layer is not formed but a compact layer. Compact layers can also be formed with thicker deposits if the decomposition of the blocked extender is faster than the reaction rate between the isocyanate and amine groups. This fact can be significantly influenced especially by the content of the modifying component, which is polyvinyl chloride. Polyvinyl chloride, especially with the addition of a plasticizer, functions in certain proportions as an important part of the composition. At lower temperatures, some gelling plasticizers increase the viscosity of the composition; By suitable selection of the plasticizer or mixture thereof, at elevated temperature, preferably below the decomposition point of the blocked extender, the viscosity of the deposit by heating is reduced to such an extent that carbon dioxide easily escapes from the mixture. By selecting the amount of polyvinyl chloride, the amount of plasticizers and their type, with appropriate selection of the blocked polyamine, various porous or completely non-porous layers can be formed. '

The physical properties of the cured layer may be. modified by adding polyols or polyhydric alcohols to the reactive mixture. Their quality and quantity during the preparation of the thermoreactive mixture and during its application adjust the viscosity behavior of the mixture. Especially those polyols which have a more pronounced hydrophilic component exhibit a reduced viscosity.

However, the addition of polyols in the mixture does not only have this clearly viscous effect on the thermoreactive mixture. It can be shown that by using a more suitable polyamine, an ester type polyol can be subjected to aminolysis, but this may not appear to be a degradation factor in the overall properties. Indeed, in certain proportions, the mixture undergoes a thermally initiated re-amidation reaction in which polyamide structures are formed:.

/-0R.00C R _o C0— / + / H _O NR KEL · / -> HO R. OR + / -NH-R -NH.CO R. CO- /

2 yy 2 x 2 y 1 x 2 ¹ y

These polyamide structures, depending on the amount in which they are formed in the reactions, also proportionally affect the physical-mechanical and thermal properties of the polymer layer. Their presence results in an increase in the tensile strength values as well as an increase in the stiffness and melting point.

However, polyols, including polyhydric alcohols, may also be involved in the formation of polymer structures by their hydroxyl groups, where by reaction with isocyanates terminated by prepolyymers, they may form branched to crosslinked spatial polymeric formations, stiffening and strengthening the cured porous layers.

Equally important is the influence of polyols on the layer structure. It was found that all the previous factors in conjunction with the surfactant. The poxisated polyols also have a considerable effect on the surface quality of the thin deposited thermosetting layers. The addition of polyols, or polyhydric alcohols, causes the surface layers which are heated first and fastest to also begin to cure first by reacting the deblocked amines with the isocyanate-terminated prepolymers. Increasing the temperature decreases the viscosity of the reacting mixture in which the hydroxyl polyol terminates as another viscosity reducing factor. At this time, the surface layer behaves as a separate micro-body from which carbon dioxide is formed by deblocking, easily flowing, so that the surface is more or less closed.- »a structure that solidifies with the reaction of hydroxyl groups of polyols, with polyvinyl chloride. The resulting surface cured formation has a worse thermal conductivity than the liquid thermoreactive composition and thus again contributes to slowing the heating and hence the reaction in the downstream layers. Once even in these layers the reaction is exothermic, the microscale will penetrate the mixture by heat accumulation to a layer having an insulating layer of cured polymer. The whole process takes about 30 seconds and actually takes place symmetrically with a certain delay due to the poor conductivity of the release paper and the underside of the coating. By virtue of this mechanism, a foam layer construction is always provided, which always has more pores in the center of the layer than the edge layers which, by their structure, also provide a better strength character of the foam structure.

The reaction mixtures according to the invention are particularly suitable for the production of deposited and bonded plastic skins for clothing, footwear upholstery, haberdashery, for the production of rigid to very soft and flexible laminates and self-supporting foils, or for the preparation of molded cast cellular breathable or liquid-permeable inserts. for filtering equipment, thermal or acoustic insulation layers, for the preparation of heat-curable thin compact coatings or lacquers.

The following non-limiting examples serve to illustrate the invention in more detail.

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Into polyoxypropylene glycol of mol. wt. 2,000 heated to 90 [deg.] C., a dry nitrogen stream was introduced under vacuum until all the water contained in the polyoxypropylene glycol was removed. After weighing 100 parts by weight, 17.4 wt. parts of toluene diisocyanate and the mixture was heated with stirring for 3 hours. After this time, the isocyanate group content was determined to be 3.48%. The mixture thus prepared was cooled to 30 ° C under stirring under a nitrogen atmosphere, and 5.06 wt. parts of ethylenediamine carbamate,

0.66 wt. parts by weight of diaminobutanecarbamate, 0.25 wt. parts of polyethylene glycol adipate having a molecular weight of 1,000, 128.25 wt. parts of polyvinyl chloride suspension having a K-value of 70.4 wt. parts by weight of a surfactant from the group of water-soluble organosilicon compounds; parts of finely ground pigment. It was stirred initially at 100 rpm for 10 minutes, then for 30 seconds at 3000 rpm. The resulting homogeneous mixture was heated with stirring and therefore had to be cooled by the jacket so that the temperature did not exceed 1 and 60 ° C. The finished mixture was degassed briefly, poured onto the applicator and applied with a 0.2 mm knife. Curing was performed at 152 ° C for 2 minutes, the cured layer having a thickness of 0.6 mm on the incision. The unit had the following mechanical properties compared to the same mixture without polyvinyl chloride:

The mixture without polyvinyl chloride is m, weight

Tensile strength

Tear strength

Example 2

336 0.64 3.67

350 kg / m ³ 0.93 MPa 1.76 N

Dehydrated polyoxypropyleneglycol of mol. wt. 1 200 in an amount of 150 wt. parts were mixed with 12.5 wt. parts by weight of diisocyanate-di-phenylmethane and 34.8 wt. d. toluene diisocyanate, with stirring, slowly warmed to 90 ° C under a nitrogen atmosphere at which it was reacted for 3 hours.

After this time, the content of isocyanate groups was determined to be 5.2 Z. The prepolymer was cooled to 30 ° C and a pre-mixed premix composed of 4.8 wt. parts by weight of water-soluble surfactant to which 1 wt. a portion of the metal-complex ester-soluble dye of azoadium; this mixture was then supplemented with 64.6 wt. parts of polybutylene glycol adipate with OH number 56 and introduced into the basic solution. Hexamethylene carbamate 19.6 wt. and ethylene diamine carbamate 32.3 wt. d. Mix thoroughly with 3.23 wt. d. Erythrocytic polyvinyl chloride. The bulk mixture was introduced into the base mixture with stirring, mixed for 20 minutes at 60 rpm and finally for 2 minutes at 2500 rpm.

A 0.3 mm layer of release paper was prepared from the blend with a knife, which cured at a rate of 1.5 mm at 14 ^° C.

Characteristics of the resulting porous coating:

Porous layer thickness Bulk density Tensile strength Tear strength

0.64 mm 303 kg / m < 0.83 MPa 1.72 N / mm

Example 3

Dewatered mixture 41 wt. d. Polyoxypropylene glycol and 7/30 polytetramethylglycol having an -OH value of 56 were mixed with 7.14 wt. d. toluene diisocyanate, heated to 80 ° C and allowed to react for 4 hours with stirring. Determination of the isocyanate groups gave 3.42 Z. A mixture of 21.32 wt. d. octylphthalate with 20 wt. d. Solvate polyvinyl chloride having a K-value of 75, which was left for 30 min, to which 0.3 wt. d. pigment, 1.5 wt. d. a silicone surfactant and 10 wt. d. kaolin having a grain size below 10 .mu.m. The mixture thus prepared was finally mixed on a mixer with a peripheral speed of 1800 m / min, after which 48.2 wt. d. prepolymers. Final mixing of the mixture was performed at 100 rpm, while maintaining the temperature of the mixture below 40 ° C and the pressure in the mixer at 400 Pa. The homogeneity of the mixture was monitored by coating the test sample on a glass sheet with a 0.1 mm thick knife. No inhomogeneities were observed in the sample when observed against light. The cured sample showed a significantly increased proportion of plastic component and suppression of asthma character by subjective evaluation to the touch.

Example 4

Polyoxypropylene glycol with OH number 56 and polyoxyethylene glycol with an average molecular weight of 600 were mixed in a three-necked glass flask at a ratio of 286: 713. After heating to 100 ° C, the mixture was dewatered by vacuum distillation at 200 Pa. The water content was determined by the Fischer method and gave a value of 0.008% moisture in the polyols.

Then, the mixture was cooled to 32 ° C, weighing 1 kg of the mixture into a flask equipped with a stirrer and a dry carbon dioxide glass introducer. 73.1 g of triethylenetetranine were introduced into the mixture thus prepared and introduced into the carbon dioxide mixtures with stirring until the reaction to the amino groups disappeared. The mixture was then heated to 60 ° C, charged with 500 g of molten diphenylmethane 4,4'-diisocyanate and allowed to react until the hydroxyl groups disappeared. The resulting white blue emulsion was stable and did not sediment.

2 g of diethyl hexyl phthalate, 6 g of powdered pigment, 40.8 g of finely ground barium sulfate, 20.4 g of polyvinyl chloride having a K-value of 74 and 30.6 g of polyoxyethylene glycol are weighed into this emulsion. The mixture was homogenized at 60 rpm for 30 minutes.

Coating with a 0.3 mm thick knife on release paper gave a solid film with fine regular pores and a very soft feel after 1 minute curing at 145 ° C. The porous film had a thickness of 0.6 mm and copied the separation paper sample very well.

Example 5

Dehydrated mixture of polyoxyethylene glycol of average mol. wt. 600, polyoxypropylenetriol with mol. weight 3 500 and polytetramethylenadipate with mol. % by weight 1000, mixed in a ratio of 6.48: 35.35: 13.94, in an amount of 55.77 wt. parts were mixed with 3.6 wt. parts of diethylenetriamine, and with stirring, the mixture was bubbled with dried carbon dioxide for 2 hours at 0.1 wt. part of carbon dioxide in 30 minutes. After 2 hours, the reaction was free to amino. group negative, 40 wt. At this temperature, the reaction mixture was maintained for 4 hours under a nitrogen atmosphere with stirring. The free isocyanate group content determined after this time was 4.8.7% by weight. 13.94 wt. d. polytetramethylene glycoladipate with mol. weight 2,000 was mixed with 7 wt. parts of polyvinyl chloride sieved through a sieve with a mesh size of 0.06 mm 1.04 wt. pigment parts, 3.48 wt. parts of calcium carbonate and 1.4 wt. parts of the iconic surfactant, water-soluble surfactant are gradually blended into a white emulsion of the prepolymer with the extender. The resulting homogeneous paste was coated with a 1.2 mm knife on release paper and after curing at 150 ° C for 1 minute a solid, non-tacky 3.5 mm thick porous layer having a tensile strength of 37% compared to the samples without adipate addition. higher and subjectively evaluated stiffness was significantly increased, without applying, appreciably the proportion of plastic component.

Claims (3)

1. A reactive composition allowing to achieve a wide variability in the properties of the resulting polymer mass formed by the additional heat treatment of a reactive composition comprising as one of the constituents a reactive prepolymer which is an addition product of a polyol, especially a polyethylene or polyester with a polyisocyanate, aromatic, aliphatic. %, cycloaliphatic or mixtures thereof, wherein the chains of the addition product have a reactive isocyanate ending, characterized in that it comprises a polymeric modification component, which is polyvinyl chloride, in an amount of 1 to 50% by weight. and a blocked polyamine extender which is an adduct of a polyamine or polyaluminum amide of an aliphatic or cycloaliphatic nature, or mixtures thereof with carbon dioxide. 2. A reactive mixture as claimed in claim 1, comprising an addition of 0.1 to 20 wt. plasticizers based on aromatic and aliphatic dicarboxylic acid esters or inorganic acid esters or mixtures thereof, or a polymeric plasticizer based on glycol or diphenyl derivatives, or mixtures thereof. 3. A reactive mixture as claimed in claim 1, comprising from 0.1 to 20 wt. polyols, especially polyether or polyester, polyhydric alcohols, optionally derivatives or mixtures thereof, wherein the polyol contains reactive hydroxyl groups.