Patent Application
20080306191
The object of the invention is a new hybrid resin containing polyisocyanate and/or blocked polyisocyanate, water glass and organic phosphoric acid ester and/or another polymer plasticizer, having improved mechanical and fracture mechanical properties, which contains vinyl ester and/or polyester as resin component. The invention also relates to a liquid system comprising two or more components for the preparation of the hybrid resin, a composite produced using such hybrid resin and the processes for producing the hybrid resin and the composite.
The resin according to the invention belongs to the family of the complicated copolymers containing polyisocyanate/water glass, which has been constantly growing ever since the late 1970s. These copolymers have several advantages over the usual organic copolymers, firstly because of the crosslinking reaction producing them may also take place in aqueous medium, secondly these products are significantly more flame retardant than the similar polymers not containing silicic acid derivatives. The reproducible preparing of these crosslinked polymers however raises some difficulties. The other problem is that the size of the polysilicic acid/polysilicate particles dispersed in the matrix varies in a wide range (20 to 200 μm); therefore the structure of the polymer is inhomogeneous. As it is known, the smaller the main particle size of the filler material of these filled polymers and the finer their distribution, the better physical-mechanical properties these polymers have. The result of dispersing water glass in polyisocyanates is an unstable, reactive water-in-oil type emulsion. Polyisocyanates with water form polycarbamid type groups. During the reaction carbon dioxide is formed and reacts with the alkali content of the water glass (aqueous solution of alkali-silicates), producing polysilicates, as a result of which the water glass ‘gelates’. The water glass drops form gel balls, which take place finely dispersing in the continuous organic matrix. As times goes on (in days, weeks) these lose water and form solid xerogel balls, while ring-shaped holes generate between the walls of the matrix and the surface of the xerogel balls [see Oertel, G., Polyurethane, Kunststoff Handbuch, 7, 34 (1993) Hanser, München]. Since the reaction of forming polycarbamid is hardly influenceable, repeating the production of the product mentioned above raises difficulties, forming of the product finishes quickly, in higher amount the system may reach 100° C., and the water vapor may cause uncontrollable foaming.
Therefore the research of polyisocyanate/water glass based systems has mainly focused on controlling the reaction speed, to improve the mechanical properties and to reducing the size of the dispersed polysilicic acid/polysilicate particles.
Patents HU 212 033 and U.S. Pat. No. 5,622,999 disclose a process to control the reaction speed in water-in-oil type emulsion of water glass/polyisocyanate using certain phosphoric acid esters. According to the mentioned documents the used aliphatic and aromatic organic phosphates serve not only as softener but also as interfacial catalysts (co-catalysts). The produced resins have been named 3P resin by their inventors from the initials of the English name of the three components (polysilicic acid, polyisocyanate, phosphoric acid ester). By the methods explained in these documents it is possible to appropriately control the reaction time between a few seconds and a few hours, also to significantly reduce the size of the formed polysilicic acid/polysilicate particles, but the diameter of the xerogel balls still varies in too wide a range, between 5 to 50 μm. A further disadvantage of the product is that a part of the phosphoric acid esters used during the process may disengage from the obtained resin, damaging the environment.
International Patent Application WO 13/016370 relates to the production of polysilicic acid/polyurethane nanocomposites by reacting polysilicic acid with polyisocyanate by adding appropriate polyols. The main idea of the aforementioned patent application is to create compatibility between the hydrophilic polysilicic acid and the hydrophobic organic components with the use of hydrophilic polyols. The size of the drops in w/o emulsion is meant to be reduced with different emulgators capable of modifying the interfacial tension. The additives that reduce the size of the drops and increase their stability however significantly influence the polyisocyanate/polyisocyanurate transformation (trimerisation) and the water/polyisocyanate (polycarbamide formation) reactions, the reactions may become uncontrollable.
The aim of the invention is therefore to provide a process and a product where the water glass/polyisocyanate reaction is controllable and the product has improved physical-mechanical properties as a result of the significant reduction of the size of the polysilicic acid/polysilicate particles. With the use of blocked polyisocyanates the work health and environment protection problems can also be significantly reduced.
We have recognized that by adding crosslinking vinyl ester and/or polyester resin to water glass and polyisocyanate (and to the usual additives of these systems), i.e. to 3P resin crosslinked hybrid resin is formed (that is a crosslinked product which consists of polysilicate particles in a hybrid polymer matrix of polyisocyanate, vinyl ester and/or polyester) with improved mechanical properties, in which the size of the majority of the polysilicic acid/polysilicate particles is smaller than 10 μm. The invention is based on this surprising recognition.
The aforementioned finding is surprising because vinyl ester resins are not compatible with water glass, they don't form a homogeneous and transparent solution. Also surprising is that reducing the size of the particles isn't obtained in the known way of adding surfactants but by adding vinyl ester and/or polyester resin.
It was also unexpected that the copolymerization of vinyl ester and/or polyester resin with unsaturated monomers and the parallel reaction between water and polyisocyanate don't affect each other significantly.
It is a fact though that the alkalinity of the water glass component accelerates the decomposition of the peroxide initiators and this has to be taken into consideration when selecting the composition and the amount of the initiator system. The amine compounds resulting from the forming of polycarbamide usually activate the radical copolymerization of vinyl ester resins. This acceleration is negligible as compared to the acceleration due to the water glass according to our experience.
The object of the invention is a liquid resin mixture for the preparation of a hybrid resin with improved mechanical properties, comprising two or more components consisting, after homogenisation, of water glass, polyisocyanate and/or blocked isocyanate, organic phosphoric acid ester and/or other plasticizers, and optionally the usual additives of these systems, which is characterized in that it further contains vinyl ester and/or polyester resin which crosslinks with unsaturated monomers. This liquid resin mixture is sometimes called “starting hybrid resin” in the present description.
A further object of the invention is a crosslinked hybrid resin obtained after the reaction of the above components which consists of a hybrid polymer matrix obtained by the linking on the one side of the reaction products of the polyaddition of polyisocyanate and/or partly or totally deblocked polyisocyanate molecules (in case of blocked polyisocyanate) and on the other side of the reaction products of the radical polymerisation of vinyl ester and/or polyester molecules, wherein the matrix contains finely dispersed polysilicate particles therein.
The inventions also relates to a process for producing such hybrid resins, to composites formed with such hybrid resins and to the production thereof.
The hybrid resin—as also the starting hybrid resin—according to the invention contains advantageously 5 to 90, more advantageously 10 to 75 parts of vinyl ester and/or polyester resin.
According to the invention vinyl ester resin means ester type compound containing one or more carbon-carbon double bond obtained from the reaction of hydroxyl compounds or the precursors thereof, advantageously epoxy compounds with carboxylic acids, advantageously unsaturated mono carbon acids. This vinyl ester resin can be crosslinked by radical copolymerization with unsaturated monomers, containing at least one carbon-carbon double bond. From the epoxy compounds used as a component the following examples can be mentioned: bisphenol-A-diglycidylethers, bisphenol-F-diglycidylethers, tetrabromo-bisphenol-diglycidylethers, other diglycidylethers, cycloaliphatic epoxy resins, epoxidized vegetable oils and epoxy novolacs. From the mono carboxylic acids reacting with the epoxy compounds we may mention the following ones as examples: acrylic acid, methacrylic acid, crotonic acid and cinnamic acid. The hybrid resin according to the invention may also contain modified vinyl ester resins, for example the ones containing urethane bonds. Vinyl ester resin may also be obtained by the addition reaction of aromatic dicarboxylic acids, tricarboxylic acids and epoxypropylmethylacrylate [see also Brian Craig: thesis, Virginia Polytechnic Institute and State University, USA (2001)], the hybrid resin according to the invention may also contain these vinyl esters.
In the hybrid resin according to the invention bisphenol-A-based vinyl ester resin, novolac based vinyl ester resin, epoxidized soya oil based vinyl ester resin are advantageous as vinyl esters. Vinyl ester mixtures, for example the mixture of a bisphenol-A based vinyl ester and a novolac based vinyl ester or the mixture of a bisphenol-A based vinyl ester and an epoxidized soya oil based vinyl ester are also advantageously used.
From the polyester resins suitable for the manufacture of the hybrid resin according to the invention mainly the polyester types disclosed in Hungarian patent 208332 can be taken into consideration, the acid number of which is preferably smaller than 40 mg KOH/g. These polyesters are obtained by the polycondensation of dicarboxylic acids such as isophthalic acid, maleic anhydride, fumaric acid, phthalic anhydride, adipic acid, sebacic acid, etc. and dialcohols, like ethylene glycol, 1,2-propylene glycol, diethyleneglycol, dipropyleneglycol, neopentylglycol, etc.
Apart from these any polyester resin is appropriate according to the invention, which has been developed for PE-PUR (polyester-polyurethane) hybrid resins by the different manufacturers. From these we mention as examples the isophthalic acid, ortophthalic acid and terephthalic acid based polyesters sold under the name Viapal by Vianova. The mixture of vinyl ester and polyester is also advantageously used in the hybrid resin according to the invention. Advantageous is for example the mixture of a modified vinyl ester containing urethane bonds and an isophthalic acid based polyester resin.
Crosslinking of vinyl ester and/or polyester resin is a result of radical copolymerisation. For this—amongst others—one or more following monomers containing one or more unsaturated bonds may be used: styrene, divinylbenzene, methacrylates, such as tetrahydrofurfuryl-methacrylate, n-hexylmethacrylate, 2-ethylhexylmethacrylate, isodecylmethacrylate, cyclohexylmethacrylate, benzylmethacrylate, hydroxyethylmethacrylate, hydroxypropylmethacrylate, diethyleneglycol-dimethacrylate, butanediol-dimethacrylate, polyethylene glycol-dimethacrylate, trimethylpropane-trimethacrylate, N-vinyl-pirrolydone, ethyl-cinnamate, dibutyl-maleate, triallyl-cyanurate, triallyl-isocyanurate, benzylidene-acetone, benzylidene-acetophenone, diethylfumarate, etc.
These monomers are also capable of solving the mostly solid vinyl ester or polyester basic resin so that they can be commercialized as solutions. These solutions usually contain 50 to 80% by weight of vinyl ester and/or polyester basic resin and can be well used for the preparation of the hybrid resin according to the invention. The hybrid resin according to the invention contains advantageously 2 to 45 parts of such monomer. In the liquid resin mixture according to the invention the component containing vinyl ester and/or polyester in solution in the unsaturated monomer compound is also called Component A1.
Since the vinyl ester and/or polyester resin is capable of self-polymerisation e.g. on the effect of heat, light, etc., the compound containing one or more unsaturated bond, used for crosslinking the vinyl ester and/or polyester resin may optionally be omitted.
VE-PUR or PE-PUR hybrid systems containing vinyl ester(VE) and/or polyester (PE), styrene and polyisocyanate are already known, for example patent application EP 0 448 167 discloses the preparation and use of such a system.
As starting compound for the polyisocyanate component according to the invention for example the following compounds and the mixtures thereof may be used:
The most important isocyanate family is the methylenediphenyl-isocyanate (MDI) family which is also the most important basic component of polyurethane (PUR) manufacturing. The so-called monomer MDIs belong to the MDIs, these contain two aromatic rings, such as the pure 4,4′-MDI, the mixtures of 4,4′-MDI and 2,4′-MDI are like that, so are the more complicated isomer and oligomer mixtures, for example the members of the crude MDI (CR-MDI) series, the viscosity of the ones available in commerce being approximately between 150 mPas and 3000 mPas. The members of the group with higher viscosity have a greater ratio of oligomer MDI with three or more rings, these are also known as polymer MDI (P-MDI). The use of P-MDI types is particularly advantageous for the hybrid resins according to the invention, but they are also advantageously used for 3P resins. The next group of MDI-which may be used according to the invention is the group of MDI pre-polymers, like the diisocyanates formed by the reaction of MDI and polyether- and/or polyester-polyols, where one MDI molecule reacts with each of the hydroxyl groups at the end of the chain. By changing the length of the chain and the chemical properties of the starting polyol—similarly to the PUR products and the 3P resins—the properties of the hybrid resins according to the invention can also be controlled. By using polyols with longer chains (Mn≧1500) the flexibility and the ductility of the product can be improved.
For the hybrid resins according to the invention the so-called modified MDIs can also be used, in these a part (e.g. 5 to 25%) of the monomer or oligomer molecules are transformed. MDIs containing carbodiimide, uretdion and urethonymin bonds and MDIs partially joint to polyisocyanurate rings by trimerization (PIR-MDI) can also be used, with the latter particularly heat and chemical resistant products can be produced.
A further group of the isocyanates which may be used according to the invention is the group of the so-called blocked (protected) isocyanates, where the reactive isocyanate groups are temporarily protected. In pure state, or in water glass free systems over 100 to 120° C., so at relatively high temperature the protective groups split off, liberating the isocyanate groups. Several such products are available in commerce, in these isocyanate is protected for example with caprolactam, dimethyl-pyrazole, diethyl-malonate, etc.
Isocyanates protected with the blocking agents disclosed in Hungarian patent application P0401799 can be advantageously used as blocked isocyanates. According to the invention particularly advantageous are the isocyanates protected with unsaturated blocking agents, for example aceto-acetic acid-ethylene glycol-acrylate or -metacrylate, mesityloxide-oxime, etc, since the unsaturated compounds splitting off from these partially build into the hybrid resin. In smaller amount isocyanate blocked with saturated compounds can also be used, where the leaving compound—similarly to the part remaining from unsaturated compounds—behaves like plasticizer.
With the use of such blocked isocyanates according to the invention hybrid resins can be formed which in case of low water glass content and with the right blocking agent are stable for a longer period of time (at least several hours) then react slowly at room temperature. In case of systems containing water glass in higher concentration though the deblocking may be finished in 10 to 60 minutes even at room temperature. This finding, i.e. that in the presence of water glass blocked isocyanate can be deblocked even at room temperature greatly widens the circle of blocked isocyanates that can be used according to the invention.
Apart from the MDI family pre-polymers, modified and blocked derivatives made of toluoylene-diisocyanate (TDI) can also be advantageously used.
For the hybrid resin according to the invention isocyanate mixtures are advantageously used, for example the mixture of polymethylene-polyphenyl-isocyanate, MDI and its polycyclic oligomers, and an MDI and polyether diol based prepolymer, or blocked isocyanate mixture, for example the mixture of MDI blocked with mesityloxy-oxim, MDI blocked with aceto-acetic acid-ethyleneglycol-methacrylate and polyether diol based prepolymers. The mixture of blocked and non-blocked isocyanate is advantageously used, for example the mixture of polymethylene-polyphenyl-isocyanate, MDI and its polycyclic oligomers, MDI partially blocked with aceto-acetic acid-ethyleneglycol-acrylate and MDI prepolymer blocked with aceto-acetic acid-ethyleneglycol-methacrylate. Also advantageous is the mixture of polymethylene-polyphenyl-isocyanate, MDI and its polycyclic oligomers and two types of blocked isocyanates, for example MDI blocked with mesityloxy-oxim and MDI blocked with aceto-acetic acid-ethyleneglycol-methacrylate.
The hybrid resin according to the invention contains advantageously 2.5 to 65 parts, even more advantageously 10 to 55 parts of polyisocyanate and/or blocked isocyanate.
According to the invention advantageously the aqueous solution or the mixture thereof of different lithium-, sodium- and potassium-water glasses are used as water glass. The modulus of the alkali water glasses (M=SiO2/Na2O) is between 1.8 and 2.9 and the viscosity at room temperature (η22° C.) is approximately between 50 mPas and 1500 mPas, advantageously between 400 mPas and 800 mPas. The hybrid resin according to the invention contains advantageously 2.5 to 45 parts, even more advantageously 8 to 35 parts of water glass. In the liquid resin mixture according to the invention the component containing water glass is also called Component A2.
Different additives are also used for the hybrid resin according to the invention.
To these additives belong the inorganic and organic percompounds generally used to initialize the radical crosslinling reaction of vinyl-ester resins, such as peroxides, organic azo- and azine-compounds and similar compounds. From the organic peroxides for example tert-butyl-peroxy-pivalate, lauryl-peroxide, dibenzoyl-peroxide, tert-butyl-peroxyisobutyrate, tert-butyl-perbenzoate, dicumile-peroxide, methyl-ethyl-ketone-peroxide and similar compounds are advantageous. The inorganic percompounds are soluble in water glass, therefore these initiators can be added to the water glass component. From these sodium and potassium persulphate, sodium perborate, hydrogen peroxide, etc. can be advantageously used. According to the invention the combination of more than one radical initiator can also be used. Advantageously 0.002 to 2 parts of initiator is used for the hybrid resin according to the invention.
As activators for the radical copolymerisation the known amine compounds can be used, from which we mention N,N-diethyl-aniline, N,N-diethly-acetoacetamide and N,N-dimethylamino-metacrylate as examples.
Fluid water glasses can also contain further additives, such are for example the polyhydric alcohols, which are soluble in water glass, for example ethylene-glycol, glycerol, etc, certain surface active agents, for example quaternary ammonium-hydroxides, coloring agents and/or pigments, thixotropizing agents, the usual fibre or granular fillers.
The most important additives to the so-called component “B”, which contains the isocyanate are the co-catalysts that are active on the interface, to these belong first of all
the phosphoric acid esters, from which the compounds in the already mentioned patent HU 201 033 can be used advantageously, particularly advantageous are for example trimethyl-triethyl-, tributyl-, trioctyl-, triphenyl-, tritolyl-phosphate or the mixtures thereof,
the tertiary-amines, dialkyl acid amides, alkylamines, etc,
diesters, diethers or ether-esters of oligomer ether-alcohols, for example tripropylene glycol-butylether-acetate, etc,
monomers with high boiling temperature and flammability point (Flp≧100° C.), such as benzylidene acetone, benzylidene acetophenone ethyl cinnamate, diethyl fumarate, triallyl cyanurate etc. The hybrid resin according to the invention contains advantageously 5 to parts of organic phosphoric acid ester and/or other plasticizer.
In component “B” optionally surface active agents may be used, from which non-ionic surfactants are advantageous. Advantageously at most 5 parts, particularly advantageously at most 1 part of surfactant is used.
According to the invention Henkel's Perenol F40 product is advantageous.
Further additives are the filler and reinforcer materials of the composites formed with the use of the hybrid resin according to the invention, such as mineral grinds, like broken basalt or andesite, barite, talc, titanium-dioxide, graphite powder, industrial carbon black, glass-fiber rope (glass thread), fiberglass chopped strand mat, glass mat (matte), glass fabric, carbon fibre, carbon fibre fabric, Kevlar® fabric, basalt fibre fabric, etc.
According to the invention a hybrid is resin is also advantageous if it contains all components mentioned above in the amount specified as advantageous.
The hybrid resin according to the invention may contain further usual additives, such as pigments, coloring agent, etc.
The invention also relates to the process of producing the hybrid resin according to the invention. The process is carried out by mixing the components of the liquid system of two or more components containing the additives in arbitrary order. Advantageously first the vinyl ester and/or polyester resin and the water glass components (components A1 and A2) are mixed, then the component containing the isocyanate and/or blocked isocyanate (component B) is added to the obtained milk-like liquid, is homogenized with it, then the product is left to cure. In certain cases wherein component B contains only blocked isocyanate, component A1 and B may also be mixed first.
An advantageous process according to the invention is when to obtain 100 parts the followings are mixed in the necessary amount: 5 to 75 parts of one or more vinyl ester and/or polyester basic resin, 2 to 45 parts of one or more unsaturated monomers which form crosslinked copolymer with the vinyl ester and/or polyester basic resin, 2.5 to 45 parts of water glass, 2.5 to 65 parts of one or more polyisocyanates and/or blocked polyisocyanates, 0.25 to 34 parts of one or more organic phosphoric acid esters and/or other plasticizer with high flammability point, 0.02 to 2 parts of one or more radical initiators and if desired one or more usual additives, and the homogeneous mixture is left to cure.
The obtained reactive resin can be applied until not cured, i.e. a period of time defined in advance, in situ between approximately 2 to 120 minutes depending on the composition. In case of use of blocked isocyanate and vinyl ester and/or polyester this period may be even longer.
This liquid resin mixture as a system of one component can be injected, can be spread, applied onto the surface of structures as corrosion preventive coating, or mixed with particulate fillers can be used as “plastic concrete”, mold as plastic mortar, or composites can be produced from it with reinforcements by laminating, impregnating, etc.
The composites can be produced in a known matter, for example by mixing the still not cured resin with fillers and/or reinforcements, or impregnating in case of fabric. The impregnating can be done in a known matter, for example by hand, in this case the resin is poured onto one side of the fabric, spread, and introduced amongst the fibres by tapping, then the fabric is turned to its other side and this operation is repeated. If desired multiple layer composites can be produced by putting several impregnated glass fabrics onto each other and squeezing the air out from amongst the fibres. The finished sheet is allowed to stand at room temperature then heat-treated.
The hybrid resins according to the invention have the following advantages over the vinyl ester, polyester and 3P resins, which form their base:
Now we will illustrate the invention with examples, it is not intended though to restrict the scope of claims with them.
The following abbreviations will be used for the starting compounds in the examples:
Polyisocyanates (products of BorsodChem. Rt. [Kazincbarcika, Hungary]):
P-MDI1: Ongronat CR 30-40, the mixture of polymethylene-polyphenyl-isocyanate, 4,4′-diphenyl-methane-diisocyanate (MDI) and of its polycyclic oligomers having greater functionality, its viscosity on 20° C. is approximately 400 mPas.
P-MDI2: Ongronat CR HV, its viscosity on 20° C. is approximately 1500 mPas.
MDI-prep: Ongronat PA 08, 4,4′-diphenyl-methane-diisocyanate and polyether-diol based prepolymer, its viscosity on 20° C. is approximately 3000 to 3500 mPas.
Blocked polyisocyanates (Experimental products of Polinvent, see tables 3 and 4):
BI1=MDI 44/50, half blocked with AAEA-(B01)
BI2=MDI 44 blocked with MEOO (B6)
BP1=MDI Prep., blocked with AAEMA (B3)
(B01, B6 and B3 are the labelling in patent application HUP0401799)
Water Glass: Betol 3P, Woellner Werke (Ludwigshafen, Germany), its Viscosity on 20° C. is approximately 600 mPas, its modulus is 2.
Vinyl ester resins:
From the products of DSM Composite Resins, Zwolle (The Netherlands):
VE(B1): Atlac 580 Standard, bisphenol-A-vinyl-ester resin in solution in styrene, its viscosity on 23° C. is approximately 400 to 500 mPas.
VE(B2): Atlac 580 HV
VE(N): Atlac 590 HV, novolac based vinyl-ester resin in solution in styrene
From the products of Reichhold (North Carolina, USA):
VE (B3): Dione 9800, modified vinyl ester resin containing urethane bonds and the:
VE(SO): epoxidized soya oil based vinyl ester resin which has been produced by us according to the slightly modified method of U.S. Pat. No. 4,224,369, its production is described in the Examples.
Polyester Resins:
PE (V): Viapal VUP 4812 B/60 (Vianova) special, isophthalic acid based polyester, preferably without amine accelerator,
PE (H): Urepol 20 (Nitrokemia) special, isophthalic acid based polyester, preferably without amine accelerator.
Interfacially active catalysts:
TBP: tributyl-phosphate
TPP: triphenyl-phosphate
TTP: tritolyl-phosphate, all three are the product of Bayer AG, Germany
PL: Mixture of TPP and TBP type plasticizers in a ratio of 1:2
Initiator:
BPO: dibenzoyl-peroxide, Lucidol CH 50 L, product of Akzo Nobel, its active peroxide content is 50%.
The hybrid resins according to the examples are produced by the use of the following components: Component A1 is the vinyl ester and/or polyester resin or resin combination in solution in unsaturated monomers, component A2 is the water glass and component B is the compound containing the MDI or MDI combination and/or blocked isocyanates and the phosphoric acid ester(s) and/or other plasticizer(s). The organic peroxide indicator can be added to either component A1 or B.
In the examples first of all the organic indicator is added to component A1, then component A2 is also added and the mixture is stirred at approximately 800 to 1000 RPM for approximately 2 minutes. Component B is added to the obtained milk-like fluid and homogenized for one minute.
To determine the mechanical properties of the obtained product, to examine the crosslinked resins the recently often used linear elastic/fracture mechanical properties have been measured, these are: the critical stress intensity factor or fracture toughness (Kc) and the critical strain energy release rate or fracture energy (Go). The Kc value is the function of the tension (proportional with the force load), the Gc value is the function of the energy (so that in case of nearly identical Kc values Gc's increment means the improvement of the ductility of the material).
To determine the Kc and Gc values the method of the ESIS TC-4 work group have been used, disclosed in the following document: J. G. Williams: Kc and Gc at low speeds for polymers in “Fracture Mechanics Testing Methods for Polymer Adhesives and Composites—ÉSIS Publ. 28”, Eds: D. R. Moore, A. Pavan and J. G. Williams, Elsevier, Oxford, 2001, pp. 11-26. The measurements have been made on notched compact tension specimen (CT). These have been obtained by pouring the starting hybrid resin in an open PTFE tool, then by curing. The test pieces have been allowed to stand for 24 hours at room temperature after their production then heat treated for 8 hours at 100° C.
Vinyl ester resin is prepared from epoxidized soya oil as follows. A mixture of 320 g (1.28 moles) of epoxidized soya oil (product of Crompton Vinyl Additives GbmH) and 0.86 g of inhibitor is heated to 100° C. with air flow and stirring and refluxing. Then the mixture of 110.5 g (1.28 moles) of methacrylic acid and 1.1 g (0.26 mol %) of catalyst is added in 2 to 3 parts in approximately 10 minutes. The reaction mixture is stirred for 6 to 8 hours at 120° C. with refluxing. To monitor the progress of the reaction a sample is taken in every hour, from which the acid number is determined. When the acid number of the compound drops below 50 mg/KOH g, the mixture is cooled to 50° C. and an aqueous solution containing approximately 1% of NaCl is added, which is 20% of the volume of the reaction mixture, the mixture is stirred for 1 to 2 minutes, then let settle. This operation is repeated until the pH of the aqueous solution is near neutral. The water traces are removed with vacuum distillation. The acid number and epoxy equivalent value of the final product is measured.
The quantity in parts by weight and the obtained fracture mechanical data of the starting materials used in the Examples according to the invention have been summarized in Table 1. We have paid attention to that the P-MDI/water glass/phosphoric acid ester ratio is the same in the Examples. In each case 1.5 parts of initiator have been given for 100 parts of vinyl ester (this is why the hybrid resins and the vinyl ester resins together don't make 100 parts).
To make a comparison a pure vinyl ester, a hybrid resin made of it and isocyanate and a pure 3P resin have been examined. The data of the comparative examples (CE) can also be found in table 1.
The results show that the hybrid resin according to the invention has better fracture mechanical properties than it could be expected from adding the mechanical properties of the components that form it according to their ratio of concentration. For example if we compare the fracture mechanical results of examples 1 and 2 to that of Comparative Examples 15, and 19 consisting only of 3P resin respectively of vinyl ester resin, or to that of Comparative Example 17, which consists of vinyl ester—isocyanate hybrid resin, it is clear that as a result of mixing the two components the fracture mechanical properties of the hybrid resin according to the invention improve surprisingly. The Gc values are particularly interesting. Based on the low Gc values of the examined pure vinyl ester resins (below 1.0) it would have been expected that the Gc values of the hybrid resins according to the invention would be lower than that of the 3P resins. On the contrary, the Gc values increase up to 50 parts of vinyl ester, and even over that they don't decrease as expected. Similarly all the hybrid resins according to the invention have better mechanical properties than the comparable resins.
It's also apparent that the use of combinations of vinyl ester resins also produces good results.
Example 10 is repeated except that 0.5% by weight of Perenol F40 is added to the water glass component as surface active agent. The obtained results are Kc=1.4 and Gc=3.3. That means the mechanical properties, particularly the Gc value is better than in Comparative Examples 15 or 21, but we have been unable to demonstrate further decrease of the main particle size resulting from the presence of the surface active agent.
Table 2 contains the composition in parts by weight and the mechanical properties of further hybrid systems of different formulations made of two different PE resins and blocked isocyanates.
(Comparative) Examples 23 and 24 demonstrate a resin made of polyester with isocyanate, Examples 25 to 27 show the production of the hybrid resin containing polyester according to the invention.
It can be observed that also the PE-3P type hybrid resins containing water glass have significantly better mechanical properties than the PE-PUR hybrid resins.
In Examples 28 to 31 the test pieces are produced with the use of blocked isocyanates. It can be seen that also these systems containing water glass have better fracture mechanical values than the comparative formulations, which means the system also works well with blocked isocyanates, the deblocking is achieved in a short time with good efficiency. The information about the production of the blocked experimental products can be found in tables 3 and 4. (The blocking reactions themselves are well known, plus are disclosed in Hungarian patent application P0401799)
Scanning electron microscopic (SEM) photos have been used to determine the physical structure of the product and the size of the polysilicic acid/polysilicate particles. The photos have been taken of the fracture surface of the CT test pieces after the usual preparation (coating with gold to avoid static charge).
FIG. 1 shows a photo of the fracture surface of the test piece made of 3P resin in 200× magnification;
FIG. 2 is the same but in 2000× magnification;
FIG. 3 shows the fracture surface of the test piece produced according to Example 5 in 5000× magnification.
By comparing FIGS. 1 and 2 (relating to the 3P resin) to FIG. 3 (relating to the hybrid resin according to the invention produced in Example 5) it can be seen that the size of the polysilicic acid/polysilicate particles in the hybrid resin according to the invention has decreased in comparison with that of the 3P resin. This means that the improvement of the fracture mechanical values can be correlated to the finer particle size distribution.
The three main components necessary to produce the hybrid resin according to the invention can be stored for a long time, or transported in case of outside production if they are prepared appropriately. The invention also relates to such a kit. Therefore the further object of the invention is a kit for storing and transporting the 3 basic components of the staring hybrid resin, which consists of vinyl ester and/or polyester resin in solution in unsaturated monomer as component A1, water glass and optionally radical initiator and other additives soluble in water glass as component A2, polyisocyanate and/or blocked isocyanates, organic phosphoric acid ester and/or other plasticizer-like material(s) and optionally one or more organic free radical initiators and other additives as component B. In another variant, the kit consists of only two components, as component A1 containing vinyl ester and/or polyester and component B containing isocyanate in blocked form are mixed.
+EtONa = Na-ethylate
ÅVL = viscous liquid, P = paste-like
| Number | Date | Country | Kind |
|---|---|---|---|
| P0401557 | Aug 2004 | HU | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/HU2005/000086 | 8/5/2005 | WO | 00 | 2/6/2007 |
