RU2394856C1 - Photopolymer composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to preparation of reactive photopolymer compositions based on polysulfone solutions used for making coatings for various purposes. The disclosed photopolymer composition contains the following (pts. wt): polysulfone based on 2,2-bis(4-oxyphenyl)propane and 4,4'-dichlorodiphenylsulfone with molecular weight of 40000-56000 (35-50), styrene as a solvent (65-50), polyethylene glycol dimethacrylate or diacrylate with molecular weight of the polyethylene glycol link of 400-600 as a polymerisable compound (20-50) and 2,4,6-trimethylbenzoyldiphenylphosphine oxide as a photoinitiator (2-6).

EFFECT: preparation of a composition which enables faster preparation of a coating with fewer process steps, increased elasticity of photopolymer materials based on polysulfone, as well as minimisation of the amount of volatile solvent during formation of the coating.

1 cl, 2 tbl, 12 ex

Description

The invention relates to the industry of polymerization plastics, in particular to the development of reactive photopolymerizable compositions based on polysulfone (PSF) solutions, and can be used to produce coatings for various purposes.

The feasibility and possibility of invariant use of this polymer for coatings both in terms of the technology of their formation and the expansion of the range of compositions based on it, is due to the fact that it is a heat-resistant, durable structural thermoplastic with high impact strength. As for the basis of film-forming for various functional purposes, its high chemical resistance to the effects of a large number of aggressive environments is crucial. However, the production of coatings and films without the use of high temperatures and special equipment is only possible by dissolving PSF in appropriate solvents. In particular, compositions are known which are solutions of polysulfone in ketones, chlorinated hydrocarbons or polar aromatic solvents (Buller K.U. Heat and heat-resistant polymers. Translated from German / Edited by Ya.S. Vygodsky. - M., Chemistry, 1984. - 1056 p.). In addition, a known method of processing PSF by dissolving in cyclohexanone (US Pat. UK No. 2198440, MKI C08L 81/06, 1989). In accordance with these technical solutions, it is possible to obtain fine coatings and films from PSF solutions by the methods of paint and varnish technology due to the volatilization of the solvent and subsequent film formation.

However, the need to remove the solvent causes the disadvantages associated with diffusion processes that cause significant local internal stresses in the coating material. In cases of using high-boiling solvents (cyclohexanone, dimethylformamide, dimethyl sulfoxide, etc.), drying by blowing with hot air is required to accelerate the coating formation stage. In this case, increased shrinkage is inevitable. The consequence of this may be a low level of adhesive interaction between the substrate and the coating material. Due to the large share of irretrievably lost solvent, environmental and economic factors are also significant.

Compositions are known in which PSF is converted into a solution using a monomer as a polymerization-capable solvent. Styrene or its mixture with an acrylic series monomer is used in certain proportions. A bulk product is obtained by polymerization in a mass of monomers in the presence of dissolved PSF under the action of redox systems at room and moderately elevated temperatures for 16-24 hours (RF patent No. 2058339, C08G 75/20, publ. 04/20/96).

However, it is obvious that the use of such solution systems with just such an initiation method for the formation of protective layers is unacceptable due to the length of the process. Since coatings are characterized by a large area to thickness ratio, the inhibitory effect of atmospheric oxygen is a determining limitation in the polymerization on a substrate. As a result, inhibition of the process, surface stickiness and inevitable volatilization of the solvent monomer.

Known compositions based on a mixture of PSF with a molecular weight of 44300 and a diacrylate polymerization-capable compound. The components are dissolved in dichloromethane with the addition of a photoinitiator. 2,2-bis (4-acryloxydiethoxyphenyl) propane is used as the diacrylate compound, and 1-hydroxycyclohexylphenylketone is used as a photoinitiator. Samples are prepared by irrigation, aged for 12 hours at room temperature to remove the main amount of solvent and finally dried in vacuum at 50 ° C for 3 hours. Next, the samples are heated to the appropriate temperature and irradiated with a UV source with an intensity of 10 mW / cm ² in a nitrogen atmosphere. After this, depolymerization is also carried out using high pressure metal halide lamps with a light intensity in the 365 nm region of 75 mW / cm ² (Morphology and mechanical properties of polymer blends with photochemical reaction for photocurable / linear polymers / Kazutaka Murata, Takanori Anazawa // Polymer 43 (2002) 6575-6583).

The disadvantages of this analogue include the large amount of solvent used, which requires mandatory diffusion removal. By using such solution compositions, it is possible to obtain only thin films and coatings. In addition, the compositions include ethoxylated bisphenol A diacrylate with “hard” aromatic fragments of diphenylolpropane in the chain as a polymerization-capable compound. Homopolymerization products of such compounds are characterized by increased hardness and brittleness. In combination with the polysulfone phase, a high tensile strength (66-73 MPa) is achieved. At the same time, the used qualitative-quantitative combination of components negatively affects the elasticity of mixed composites with PSF.

Closest to the proposed is a technical solution on the application (JP 2001329027 from 11.27.2001, RESIN COMPOSITE, COMPOSITION, AND THEIR PRODUCTION METHODS), in accordance with which they use a linear polysulfone based on 2,2-bis (4-hydroxyphenyl) propane and 4 , 4'-dichlorodiphenylsulfone, (meth) acrylates with 2-6 (meth) acrylic groups (a), (meth) acrylates with one (meth) acrylic group (b), photoinitiator of 1-hydroxycyclohexylphenylketone dissolved in dichloromethane. The content of the latter can reach 86%.

The reasons that impede the achievement of the desired technical result when using the known solution of the photopolymerizable composition based on polysulfone include the following. Firstly, the coating is formed for a long time, in several stages, heating and vacuum are necessary. Secondly, the material does not have sufficient elastic deformation properties (elongation at break is only 7-12%). Thirdly, the amount of solvent removed is large (up to 86% of the composition).

The technical result of the invention is the possibility of accelerated coverage with fewer technological operations, increasing the elasticity of photopolymer materials based on PSF, as well as minimizing the amount of solvent escaping at the stage of coating formation.

The specified technical result is achieved through the use of a photopolymerizable composition, including polysulfone based on 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dichlorodiphenyl sulfone with a molecular weight of 40,000-56,000, a solvent, an addition of a polymerization-capable compound and a photoinitiator, different the fact that it contains styrene as a solvent, as a polymerization-capable compound of polyethylene glycol diacrylate or dimethacrylate with a molecular weight of polyethylene glycol unit 400-600, and as a photoinitiation an atom of 2,4,6-trimethylbenzoyl diphenylphosphine oxide in the following ratio of components, parts by weight:

2,2-bis (4-hydroxyphenyl) propane polysulfone and 4,4′-dichlorodiphenylsulfone 35-50 Styrene 65-50 Polyethylene glycol diacrylate or dimethacrylate with a molecular weight of from 400 to 600 20-50 2,4,6-trimethylbenzoyl diphenylphosphine oxide 2-6

The essence of the invention lies in the use of a photopolymerizable composition, the composition of which provides the ability to quickly form polysulfone-containing coatings by irradiation with available light sources while maintaining the advantages of applying the compositions according to paint and varnish technology. In this case, the inhibitory effect of atmospheric oxygen is small, since the oxygen present in the reaction mass and on the surface is capable of passing from the singlet state to the triplet (excited) state under the action of ultraviolet light quanta. As a result, its inhibitory ability is leveled, which leads to an increase in the rate of photopolymerization and the absence of surface stickiness in the material. This circumstance makes it possible to use even stabilized (untreated from the inhibitor) styrene.

The use of styrene in the composition of the composition is determined by its good dissolving ability with respect to PSF and the thermodynamic compatibility of the solution components, including with the addition of a polymerization-capable compound (PSS). Due to the fact that under the conditions of photo-induced polymerization, styrene itself turns into a high molecular weight compound and participates in the copolymerization reaction with polyethylene glycol di (meth) acrylate, the result is achieved in terms of minimizing the fraction of volatilizing solvent.

The additives of polymerization-capable compounds used in the claimed composition contribute, on the one hand, to a faster photopolymerization process due to the presence of two (meth) acrylate groups (i.e., more functionality for double bonds compared to styrene). On the other hand, the main chain in the molecules of acrylate polymerization-capable compounds that are part of the compositions of the claimed invention consists of oxyethylene units with a large number of “articulated” oxygen bridges, providing increased flexibility and elasticity to both homo- and copolymerization products and polysulfone-containing composite material obtained from the claimed photopolymerizable composition. Moreover, the totality of the achieved effects also depends on the content of di (meth) acrylate of polyethylene glycol, as well as its molecular weight (MM). Most preferably, the use of a polymerization-capable compound with an MM of a polyethylene glycol unit of from 400 to 600 in the claimed amounts. If polymerization-capable compounds with lower molecular masses are used in the photopolymerizable composition, the result is not provided with regard to the necessary physical and mechanical properties. The latter applies to materials based on PSF-styrene systems obtained with the addition of a polymerization-capable compound of less than 20 wt. hours when introduced into the photopolymerizable composition of di (meth) acrylate polyethylene glycol more than 50 wt.h. strength properties of materials are reduced.

The use of 2,4,6-trimethylbenzoyl diphenylphosphine oxide in the composition as a photoinitiator is justified by the fact that it is characterized by high photochemical activity in the region with a wavelength of more than 360 nm. This allows the use of accessible light sources with low radiation power, which do not require cooling during the insolation of the object (for example, mercury arc and tube lamps of the DRL and DRT type) and determine the practical applicability of the technical solution.

In its original form, the inventive photopolymerizable composition is a one-pack composition with an adjustable viscosity, which, provided that light is not exposed to it, has a long shelf life. When applied to a substrate and subsequent UV irradiation for 8-15 minutes, a coating is formed directly on it, which is adhesively bonded to the substrate. If necessary, materials in the form of free films up to 600 microns thick can be obtained in a similar way. Thus, the number of technological operations is minimized. There are no stages of solvent evaporation and additional heating. In general, the foregoing and determines the essence of the technical solution, which, in comparison with analogues and prototype, is more effective in terms of the result achieved.

The claimed intervals for the content of PSF and styrene are due to the following two main factors: firstly, the viscosity of the compositions, which depends mainly on the amount of dissolved PSF, must be necessary and sufficient for applying the compositions by paint and varnish technology; secondly, since the properties of the material obtained are largely determined by the concentration of the initially dissolved PSF, it is preferable that the content of the latter in the formulation be as high as possible.

If the amount of dissolved PSF is less than 35 mass parts, it is possible to obtain technologically advanced low-viscosity solutions, but they are prone to swelling from inclined and vertical surfaces, and the photopolymerization products have the worst set of properties. In cases where polysulfone is used in the compositions more than in the claimed ratio, they are characterized by a sharp increase in viscosity. Such polysulfonyl styrene systems are potentially unsuitable for coating formation by methods used in paint and varnish technology. In General, for these reasons, compositions containing less than 35 and more than 50 mass parts of PSF are not illustrated by examples.

According to the invention, the product of the interaction of the disodium salt of diphenylolpropane (bisphenol A) and 4,4'-dichlorodiphenylsulfone (TU-6-06-66-88) with a molecular weight of 40,000-56,000 and with the following structural formula of the elementary unit is used as polysulfone:

The photoinitiator is 2,4,6-trimethylbenzoyl diphenylphosphine oxide manufactured under the Esacure TPO brand name

The following products are used as polymerization-capable compounds:

Polyethylene glycol dimethacrylate with a molecular weight (MM) of PEG unit 600, n = 14

Polyethylene glycol diacrylate, with a molecular weight (MM) of the PEG unit 400-600, n = 9-14

The active solvent is styrene, corresponding to GOST 10003-90.

The formulations of the proposed and control compositions, as well as the prototype are shown in table 1.

Table 1 The compositions of the examples and prototype Song Components The compositions of the examples, wt. hours Proposed Control Prototype (examples 1-3) one 2 3 four 5 6 7 8 9 10 eleven 12 Polysulfone 40 35 fifty 40 40 40 40 40 40 40 40 40 3-4 Styrene 60 65 fifty 60 60 60 60 60 60 60 60 60 - Polyethylene glycol diacrylate with MM PEG link 600 thirty twenty fifty 38 - - - - - - thirty thirty - Polyethylene glycol dimethacrylate MM PEG link 600 - - - - 38 - 10 - 60 - - - - Polyethylene glycol diacrylate MM PEG-link 400 - - - - - 38 - 10 - 60 - - - 2,4,6-trimethylbenzoyl diphenylphosphine oxide four 2 6 four four four - - - - one 7 - 1-hydroxycyclohexylphenylketone - - - - - - - - - - - - 0.2-0.3 Dichloromethane - - - - - - - - - - - - 83-86 A mixture of dicyclopentanyldiacrylate with monofunctional (meth) acrylates - - - - - - - - - - - - 10-13

The invention is illustrated by the following examples.

Example 1. Use ratios close to average (preferred formulation). For this, 60 g of styrene is added to 40 g of polysulfone. Upon heating to 80 ° C and periodic stirring, a homogeneous solution is obtained. Add 30 g of polyethylene glycol diacrylate with MM = 600 and 4 g of photoinitiator (2, 4, 6-trimethylbenzoyl diphenylphosphine oxide). The mixture is homogenized and part of it after cooling is taken to determine the dynamic viscosity on a Brookfield viscometer. The other part is applied by a free-casting method in a thickness of 500-600 μm to a suspended silicone or fluoroplastic substrate and subjected to irradiation under the influence of a full spectrum of a UV light source of the DRT-400 type from a distance of 25 cm (surface energy illuminance is 40 W / m ² ) for 15 minutes. Then the substrate together with the composition is again weighed on an analytical balance and the quantity (fraction) of the volatilized component is determined by the difference in masses. Thus obtained material is peeled off and tested according to GOST 11262-80 to assess the elastic strength properties, fixing the conditional tensile strength and elongation. The properties of the solutions and photopolymerization products are shown in table 2.

Example 2. In contrast to example 1, the minimum claimed ratio of components is used. Examine the solution, cure and test the material as in example 1.

Example 3. Prepare and examine a solution of PSF in styrene, irradiate and test the material according to example 1, but use the maximum dosage of all components.

Example 4. By analogy with example 1, a composition is prepared in which 38 g (average content) of polyethylene glycol diacrylate with a molecular weight of 600 polyethylene glycol unit is introduced as a polymerization-capable compound.

Example 5. By analogy with example 4, a composition is prepared for comparison, but polymethylene glycol dimethacrylate with MM polyethylene glycol unit 600 in an amount of 38 g is used as a polymerization-capable compound.

Example 6. By analogy with example 4, a composition is prepared for comparison, but 38 g of polyethylene glycol diacrylate having an MM of polyethylene glycol unit 400 is used as the polymerization-capable compound.

Example 7. Prepare and examine the solution and material as in example 1, but the amount of diacrylate is 10 g (overseas dosage at the minimum content of PSS).

Example 8. Prepare and examine the solution and material as in example 1, but the amount of dimethacrylate is 10 g (foreign dosage for the minimum content of this type of PSS).

Example 9. Prepare and examine the solution and material as in example 1, but the amount of diacrylate with MM polyethylene glycol unit 600 is 60 g (overseas dosage for the maximum content of PSS).

Example 10. Prepare and examine the solution and material as in example 1, but the amount of dimethacrylate with MM polyethylene glycol unit 600 is 60 g (overseas dosage for the maximum content of this type of PSS).

Example 11. Get the material in accordance with example 1, but the content of 2,4,6-trimethylbenzoyl diphenylphosphine oxide in the composition is 1 g (foreign ratio of the minimum amount of photoinitiator).

Example 12. Get the material in accordance with example 1, but the content of 2,4,6-trimethylbenzoyl diphenylphosphine oxide in the composition is 7 g (foreign ratio of the maximum amount of photoinitiator).

table 2 Properties of solutions and materials obtained from photopolymerizable compositions Properties of solutions and materials Photopolymerizable compositions of the examples proposed control prototype one 2 3 four 5 6 7 8 9 10 eleven* 12** Dynamic viscosity at 20 ° С, Pa · s 12,4 5,0 210.0 10.0 22.6 9.3 29.3 33,2 16,0 18.1 12,4 12,4 2-9 The fraction of the volatilized component,% 1,0 4.0 1,0 1,5 1,5 1,6 2,4 2.5 1,0 1,0 eighteen 0.7 83-86 Tensile strength, MPa 29.8 16,0 35.0 31,4 29.1 31.9 23,2 18.0 14.6 13.6 - - 46.0-68.0 Elongation at break,% 45 60 fifteen 22 twenty fifteen 12 9 65 twenty - - 4.3-10.3 The time required to form a coating from the finished solution, min fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen fifteen - 2 > 180 * Material is not formed in 15 minutes of exposure due to the low speed of the process. ** After 2 minutes of irradiation, a “shagreen” layer forms from the surface due to the high photopolymerization rate; the material is defective and has no technical value.

The data in table 2 indicate that the viscosity of the solutions (and therefore their manufacturability) can be regulated by changing the ratio of components within the claimed. By using solutions of PSF in styrene with the addition of PSS and a reasonably selected photoinitiator, it is possible to obtain materials whose formation process, in contrast to the prototype composition, is characterized by a minimum fraction of volatile components. The creation of material from the proposed mortar composition does not require a special supply of heat from the outside and the use of vacuum for the diffusion separation of the solvent. The number of technological operations is reduced. The principal difference in terms of the technical result lies in the fact that, along with PSS, the dissolving agent under the conditions of photoinduced polymerization also turns into a polymer product, and by using di (meth) acrylate compounds of a certain nature in the indicated formulation ratios with other components, it is possible to obtain materials with relative elongation in the range of 45-60% with a sufficiently high strength properties and comparable values of impact strength. In this case, it is preferable to use diacrylates and dimethacrylates of polyethylene glycol with MM = 600, since materials have a better balance of elastic-strength characteristics.

Thus, the above information indicates the fulfillment of the following set of conditions when using the claimed invention: the agent embodying the claimed invention in its implementation is intended for use in the manufacture of coatings and free films based on solutions of PSF in styrene with additives of PSS and photoinitiator by photoinduced polymerization; for the claimed technical solution in the form described in the independent claim, the possibility of its implementation using the means and methods described above or known prior to the priority date is confirmed; means that embody the claimed invention in its implementation, is able to ensure the achievement of the perceived by the applicant technical result.

Therefore, the claimed invention meets the requirement of "Industrial applicability" under applicable law.

Claims (1)

A photopolymerizable composition comprising a polysulfone based on 2,2-bis (4-hydroxyphenyl) propane and 4,4′-dichlorodiphenyl sulfone with a molecular weight of 40,000-56,000, a solvent, an addition of a polymerization compound and a photoinitiator, characterized in that it contains styrene as a solvent , as a polymerization compound, a diacrylate or polyethylene glycol dimethacrylate with a molecular weight of a polyethylene glycol unit of 400-600, and as a photoinitiator, 2,4,6-trimethylbenzoyl diphenylphosphine oxide in the following ratio SRI components in parts by weight:
2,2-bis (4-hydroxyphenyl) propane polysulfone and 4,4′-dichlorodiphenylsulfone 35-50 Styrene 65-50 Polyethylene glycol diacrylate or dimethacrylate with a molecular weight of polyethylene glycol links from 400 to 600 20-50 2,4,6-trimethylbenzoyl diphenylphosphine oxide 2-6