CS216521B2 - Method of making the hardenable plastic substance reinforced by fibres - Google Patents

Abstract

Unsaturated is used in this process synthetic resin and / or monomer, catalyst, accelerator and reinforcing fibers. Unsaturated synthetic blend resin and / or monomer and one from the group consisting of catalyst a the accelerator is reinforced with fibers containing second substance of the same group. The curing process only begins when when synthetic resin and reinforcing the substance. This prevents undesirable gelatinizing synthetic resin increases work safety and easier operational handling.

Description

The present invention relates to a method for producing a curable fiber-reinforced plastic using an unsaturated synthetic resin and / or monomer, catalyst, accelerator system and reinforcing fibers.

Unsaturated synthetic resins and monomers such as styrene and acrylates are generally cured by the addition of accelerators and

b) a catalyst.

The plastic formed during curing is generally referred to as duroplast. To achieve improved mechanical strength of the thermoset, the thermoset is reinforced with glass or carbon fibers or the like.

The hardening of the unsaturated plastic is carried out according to both of the following mechanisms:

1. Redox system

The catalyst forms radicals by the action of a reducing agent. The most common reducing agent is cobalt ions Co ⁺⁺ . The mechanism is probably the following (Tobolsky and Mesrobian, Organ Peroxides, Wiley interscience, New York, 1954 J:

ROOH + Co2 + RO + OH “+ Co ³⁺ ROOH + Co ³⁺ -> RO ₂ . + H + + Co 2 + RO. + Co ²⁺ - RO + Co ³⁺

2. Horner-Schenk mechanism

Numerous amines form free radicals on contact with peroxides. Horner and Schenk explain this in this way [Horner and Schenk, Angew. Chemie 61, 411 (1949)]:

CH.yN CH $

o o c ^ c-o.o & c ^

O θ

OCC / ^ _S H CO

O

-OCC _s H _s -> H

Η H oH CH,

CH, i 'N:

Unsaturated synthetic resins are usually used in conjunction with monomers such as styrene and / or acrylates to achieve the desired processing and end product properties.

Generally, an accelerator is added to the synthetic resin / monomer mixture since the stability of such a system is relatively long, usually several months. In addition, stability may be controlled by the addition of an inhibitor such as hydroquinone.

A catalyst such as methyl ethyl ketone peroxide, cyclohexane peroxide, acetylacetone peroxide, benzoyl peroxide or the like is added immediately prior to use.

Until now, the accelerator and catalyst have been added to the unsaturated synthetic resin or to a mixture of such resins before the resins have been contacted with the fibers. Once the catalyst was added, curing began. The synthetic resin mixture generally gelled after 2 to 60 minutes and the article was removed from the mold after 4 to 6 hours. Optimal curing may take more than 24 hours.

In the manufacture of reinforced duroplastics, glass fibers, carbon fibers, polyamide fibers and the like are used as reinforcing agents. These fibers are dispersed and well processed into liquid unsaturated synthetic resins to which a curing system is added.

A disadvantage of the known processes mentioned is the relatively short time from the beginning of the processing of the materials to its completion, which places high demands on, inter alia, operational technology and operation. Curing, as already mentioned, begins in the prior art as soon as the catalyst and accelerator are contacted with the unsaturated synthetic resin.

These disadvantages do not occur in the process for producing a curable fiber reinforced plastic using an unsaturated synthetic resin and / or monomer, catalyst, accelerator and reinforcing fibers according to the invention, characterized in that the mixture of unsaturated synthetic resin and / or monomer and one substance from the group consisting of a catalyst and an accelerator, it reinforces fibers containing a second substance of the same group.

As a synthetic resin, polyester, polyacrylate, vinyl resin, polyurethane or other unsaturated polymerizable compounds such as styrene monomer may be used, or mixtures of said resins may be used.

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The catalyst may be a peroxide or another type of catalyst or a mixture of these catalysts may be used.

It can be accelerated on the basis of cobalt, iron, manganese, vanadium, lead, amine-based or other class of accelerators, both alone and in admixture with each other.

As reinforcing fibers, glass, carbon, metal wires, polyamide fibers or other suitable fibrous materials may be used, either in the form of unprocessed fibers or in the form of mats, rovings, woven rovings, staple fibers, or fibers in other forms .

The curing process then begins only when the synthetic resin and the reinforcing agent are brought into contact. In this way, gelation of the synthetic resin or mixture in containers and apparatus is avoided. This leads to large savings, as raw material losses are reduced, equipment wear is reduced, cleaning is simplified while reducing the consumption of organic solvents, thus improving the environment around the workplace. The risk of fire is substantially reduced, which is based on the fact that the handling of peroxides as catalysts is considerably reduced, since it is possible to mix the supply of unsaturated resin and catalyst for one day at a time. In addition, residues of the synthetic resin mixture to which both the accelerator and the catalyst are added are prevented from undergoing an uncontrollable strong exothermic curing reaction, which has so far often caused fires.

. Since the curing process starts only when the reinforcing agent is mixed with the incorporated accelerator with the unsaturated resin containing the catalyst, the operators have much more time and thus have the possibility to produce technically better products.

A glass fiber mat containing about 330 ppm of cobalt is used as a laminate reinforcing mat in which the unsaturated resin is a polyester dissolved in styrene and with the addition of 2% methyl ethyl ketone peroxide. The laminate is heated in a manner known per se. The gel formation time is about 40 minutes. Full cure was found after 9 hours. After curing at room temperature for 24 hours, the residual monomer in the laminate was found to be about 1.5%:

In the example, cobalt accelerator, methyl ethyl ketone peroxide catalyst, and unsaturated polyester resin (standard unsaturated phthalic and maleic acid based polyester dissolved in monomeric styrene are used as substitutes but these may, of course, be replaced by those specified in the definition.

Example 1

Application of the accelerator system to the primary fibers.

A. The cobalt compound or other type of accelerator is dissolved in the finish applied to the fibers immediately after drawing, incorporating into the glass fibers the desired amount of the cobalt compound or other accelerator.

Fiber size vinyltris-beta-methoxyethoxysilane 0.50 polyvinyl acetate emulsion (50% J 7.60 lubricant (Arquad S50J 0.07 cobalt acetate) [Co (C ₂ H ₃ O ₂ j _. 4 H ₂ O) 2.20 demineralized water 89.63

100.00

B. The cobalt compound or other type of accelerator is dissolved or emulsified or chemically bound with a polyester or epoxy resin as the film-forming component of the finish, then the desired amount of the cobalt compound or other accelerator is introduced into the glass fibers.

Sizing for gamma-aminopropyltriethoxysilane fibers 0.30 water-soluble polyester resin 5.50 lubricant (Cirrasol 185 A J 0.30 polyvinylpyrrolidone 1.50 cobalt octoate (10% cobalt) 4.00 demineralized water 88.40

100.00

Example 2

Application of accelerator to finished products.

A. In the manufacture of emulsion-bonded glass fiber mats, the cobalt salt or other accelerator is added in a suitable amount to the binder to obtain a glass fiber mat containing the desired amount of cobalt salt or other accelerator, a) binder for polyvinyl acetate emulsion mat (50%) 7,50 saturated polyester 3,00 cobalt sulphate (CoSO ₄ .7H ₂ 0) 0,40 emulsifier (nonylphenol polyglycol ether) 0,02 demineralized water 89,08

100.00

b) polyvinyl acetate emulsion (50%) 7.50 saturated polyester 3.00

dimethylanllin 0.40 emulsifier (nonylphenol polyglycol ether) 0.02 demineralized water 89.08

100.00

B. In the manufacture of glass fiber mat emulsions, the cobalt octoate or other cobalt compound or other accelerator is dissolved in the polyester or emulsified, dispersed or bound to the polyester by reaction. This polyester is used as a binder for a glass fiber mat so that the desired amount of cobalt compound or other accelerator is incorporated into the glass fiber mat. Binder for mat polyvinyl acetate emulsion (50% ·) 7.50 saturated polyester (based on ethylene glycol and adipic acid) 3.00 cobalt octoate (10% cobalt) 0.90 emulsifier (nonylphenol polyglycol ether) 0.02 demineralized water 88.58

100.00

C. In the manufacture of a powder-bonded or emulsion-bonded glass fiber mat, a cobalt compound solution or other accelerator solution is sprayed onto the mat by a nozzle system above and / or below the mat conveyor so that the desired amount of cobalt compound or other accelerator is incorporated into the glass fiber mat.

Spray liquid cobalt sulphate (CO 2 SO 4 .7H 2 O) 2.00 water 98.00

100.00

D. In the manufacture of a glass fiber roving, a solution of the cobalt compound or other accelerator is applied by its own coating system or in a bath, followed by drying to incorporate the desired amount of cobalt compound or other accelerator into the glass fiber roving.

Cobalt (II) sulphate solution (CoSO ₄ .7H ₂ O) 5 water 95

100 ALIGN!

In the manufacture of all other fibrous products, one or more of the aforementioned deposition methods are used.

Claims (1)

A method for producing a curable plastic, fiber reinforced using an unsaturated synthetic resin and / or monomer, catalyst, accelerator and reinforcing fibers, characterized in that the mixture of NON-BREAKING HYDROGENED synthetic resin and / or monomer and one of the catalyst / accelerator group fibers containing a second substance of the same group.