JPS6225488B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel and useful method for producing prepreg gloving, and more specifically, the present invention relates to a method for producing prepreg gloving, which is roughly divided into three steps: an impregnation step, a treatment step, and a non-sticking step. This relates to a manufacturing method.

Furthermore, the present invention uses continuous fibers such as glass fibers, carbon fibers, and polyamide fibers as reinforcing materials to provide extremely low stickiness, high elasticity, easy handling, and ease of complex secondary processing. The object of the present invention is to provide a method for manufacturing pre-pre-gloving.

Fiber-reinforced plastics (hereinafter referred to as "FRP"), which are obtained by impregnating a reinforcing material such as glass fiber with unsaturated polyester resin, molding it into a predetermined shape, and curing it, have excellent corrosion resistance. ,
Because they are lightweight and strong, they are used in a wide variety of applications, including tanks, fishing boats, pipes, bathtubs, and containers.

By the way, the general molding method for such FRP is to mold the reinforcing material while impregnating it with resin.
A molding material (prepreg) with reduced stickiness is prepared by a curing method and by impregnating the reinforcing material with resin and then performing some treatment.
There are two types of methods: one is then molded into a predetermined shape and then hardened.

Hand lay-up molding, resin injection molding, mated die molding, etc. belong to the former method, while SMC molding, BMC molding, prepreg molding, etc. belong to the latter method, and because the latter uses prepreg, Compared to the former, it has the advantage that the amount of monomer volatilization is smaller and the working environment is improved.

Note that when an external force acts on FRP, the reinforcing material bears this external force due to its structure, and the unsaturated polyester resin that is the matrix plays the role of transmitting this external force to the reinforcing material, so the reinforcing material is continuous. Continuous fiber-reinforced plastics are often used for members that require high strength and are desirable in terms of physical properties.

However, unidirectionally continuously reinforced plastics
It is molded using the FW molding method, but in such a case, the fiber content inevitably becomes high, making it extremely difficult to control the resin/fiber ratio.

By the way, "prepreg", as mentioned above, refers to a molding material in which a reinforcing material such as glass fiber is impregnated with resin and then subjected to a certain treatment to reduce stickiness. The manufacturing method involves forming a metallic bond between the carboxyl group in the unsaturated polyester resin and an oxide or metal hydrate of an alkaline earth metal such as MgO or CaO to thicken the adhesive. There is a drying method in which the resin, monomer, etc. are dissolved in a solvent in advance, the reinforcing material is impregnated with this, and the solvent is evaporated to remove the stickiness. Two methods are already known.

The present inventors initially attempted to manufacture pre-pre gloving using these two known methods, but
In fact, in the case of the former method, a long thickening time is required, and the surface tackiness of the obtained pre-pregloving is not completely removed;
For this reason, it has been found that even if temporary treatments such as powder adhesion treatments are applied, there is an inconvenience in that stickiness appears over time. Therefore, when these rovings are wound onto a bobbin, they join together, making unwinding extremely difficult and resulting in uneven unwinding tension. Furthermore, since this roving lacks elasticity, when it is wound onto a bobbin, the roving is crushed and its cross-sectional shape is flattened.

On the other hand, if the latter method mentioned above is used, that is, the method of manufacturing prepreg gloving using a solvent type, the manufacturing time can be shortened, but it is not as good as the former method in terms of deformation such as flattening and adhesiveness. It has been found that the same tendency is exhibited, and in fact, this tackiness occurs more markedly than in the former method, and it has become impossible to unwind a few days after winding. Moreover, in the case of this solvent type, since the amount of monomer is naturally reduced, the crosslinking density becomes low and the physical properties also deteriorate.

However, as a result of intensive research in view of the existence of these various drawbacks in the conventional technology, the present inventors have developed a unidirectional reinforcement with extremely low adhesiveness and high elasticity.
The present invention was completed by discovering a method for producing prepreg gloving, which is an FRP molding material.

That is, the present invention comprises () a step of impregnating a reinforcing material with an unsaturated polyester resin composition containing an unsaturated polyester resin and a polyisocyanate compound as main components; A prepreg comprising a step of controlling the amount of a resin composition impregnated into a reinforcing material, and shaping the reinforcing material after impregnation, and () a step of making the shaped impregnated material non-adhesive. To provide a method for manufacturing roving.

Here, the above-mentioned "unsaturated polyester resin" refers to a resin obtained by dissolving an esterified polycondensate of a conventional dibasic acid component and a glycol component in a conventional polymerizable monomer, and The above-mentioned "polyisocyanate compound" includes, for example, tetramethylene diisocyanate, hexamethylene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, xylylene diisocyanate, 4.
4'-diphenylmethane diisocyanate, 2.4
- Diisocyanates such as tolylene diisocyanate, 2,6-tolylene diisocyanate, and naphthalene diisocyanate; and isocyanate prepolymers with isocyanate groups added to the terminals by reacting the terminal hydroxy groups of polyester polyols or polyether polyols with diisocyanate compounds, etc. It is selected from commonly used ones such as.

As for the amount of these polyisocyanate compounds used, it is preferable that the entire amount of isocyanate groups reacts with the hydroxy groups in the unsaturated polyester resin.
The molar ratio of isocyanate groups is 1.0, but from 0.7 to
If it is within the range of 1.3, it can be used satisfactorily.

The unsaturated polyester resin composition used in carrying out the method of the present invention consists of the above-mentioned unsaturated polyester resin and polyisocyanate compound as main components, but may also contain benzoyl peroxide, methyl ethyl ketone peroxide, etc. conventional curing catalysts such as oxide, lauroyl peroxide, cumene hydroperoxide, dicumyl peroxide, t-butyl perbenzoate; conventional urethanization catalysts such as cobalt octate, dibutyltin dilaurate; calcium carbonate, clay, hydroxide. Conventional fillers such as aluminum; conventional mold release agents such as zinc stearate; other inorganic or organic pigments, low shrinkage agents such as thermoplastic resins, alkaline earth metal oxides, etc. can be added.

Hereinafter, the present invention will be specifically explained based on the drawings.

First, an unsaturated polyester resin composition containing an unsaturated polyester resin and a polyisocyanate compound as main components is placed in a resin tank 2 in advance, and a reinforcing material 1 such as glass roving is passed through the resin tank 2. The reinforcing material is impregnated with the resin composition, and then the impregnated material is subjected to shaping treatment in a drawing process using a die 3, and at the same time, the resin composition/reinforcing material ratio is controlled.

As the reinforcing material 1 used here, it is preferable to use one that has been sufficiently treated with a binder to the extent that it does not interfere with impregnation, and that the tension of the strands is made uniform, in order to prevent the prepreg globbing from becoming fluffy. It is something.

Subsequently, after passing through the die 3, the adhesive is removed by passing through a heating device set at a predetermined temperature condition, such as a heating furnace 4, and a prepreg gloving with high elasticity is obtained.

Here, the temperature in the heating furnace 4 may be adjusted in relation to the decomposition temperature of, for example, peroxide added as a curing agent to the unsaturated polyester resin, and several prepreg glovings may be manufactured at the same time. In such cases, it is recommended to provide a separating device 5 in the heating furnace 4 to prevent them from joining together.

At this time, when calcium carbonate is used as a filler in the resin composition, the effect of shortening the aging time is increased, but preferably, the obtained prepreg globbing is subjected to powder adhesion treatment in the powder tank 6. The stickiness should be removed more completely and allowed to cool.

When such powder adhesion treatment is performed continuously, tunnel-like voids are often formed in the powder, but in order to avoid this cause of insufficient powder adhesion, the powder tank 6 has a rotary structure. One way to prevent this is to use a vibrator or install a vibrator.

The prepreg gloving thus obtained is then taken off by a take-up device 7 while maintaining its cross-sectional shape, then wound up by a bobbin set in the take-up device 8, and wrapped in aluminum foil or the like.

Therefore, according to the method of the present invention, the stickiness immediately after production is extremely low, and the occurrence of this stickiness over time is not observed, so if powder adhesion treatment is applied at the time of production, it can be wound on a bobbin and stored. Even if they are left in place, they will not join together and become difficult to unwind.

In addition, since the prepreg gloving manufactured according to the method of the present invention has high elasticity, its cross-sectional shape does not change when it is wound onto a bobbin, and therefore it remains uniform during post-processing. It is possible to unwind with a certain tension, and
Since it does not flatten during post-processing, it can be processed with uniform tension and thick molded products can be obtained.

Furthermore, according to the method of the present invention, the hardness of the prepreg gloving can be adjusted by changing the amount of polyisocyanate compound used, and by changing the die shape, the cross-sectional shape of the prepreg gloving can be adjusted. The ratio of materials can also be controlled at will.

The prepreg gloving thus obtained makes it easier to mold FRP molded products such as ropes, blinds, and nets that require complex secondary processing that was considered difficult with conventional molding methods. This is particularly advantageous when molding unidirectionally reinforced FRP, where it is desirable to control the ratio and mold with tension.

Next, the present invention will be specifically explained using examples.

Hereinafter, all parts refer to parts by weight.

Example “Polylite” as an unsaturated polyester resin
ODR-485” (Dainippon Ink & Chemicals Co., Ltd. product)
5 parts of 4,4'-diphenylmethane diisocyanate as a polyisocyanate compound per 100 parts
2 parts, t-butyl perbenzoate as a curing agent
After thorough stirring, an unsaturated polyester resin compound consisting of 40 parts of calcium carbonate and 40 parts of calcium carbonate is placed in a resin bath.

Next, a glass roving of 2400 g/km is continuously passed through this resin tank to impregnate the roving with the resin compound, and the excess resin compound is squeezed out using a die with a conical inner surface to form a compound. After controlling the ratio of /roving to 50/50 (weight ratio) to shape the cross-section into a circular shape, the product is passed through a heating furnace heated to 90°C for 3 minutes to mature.

Finally, it was passed through a powder tank containing talc to perform a powder adhesion treatment, wound up onto a bobbin, wrapped in aluminum foil, and stored.

The prepreg glovings thus obtained had extremely low tackiness and did not develop tackiness over time, so they did not stick to each other even after being wound onto a bobbin and left for a long period of time.

Furthermore, since this prepreg gloving has appropriate hardness and elasticity, the cross-sectional shape itself does not become flat when it is wound onto a bobbin, and therefore it is possible to unwind it with uniform tension. .

However, when the net and FW pipe were formed using this prepreg gloving, there was almost no change and the cross-sectional shape was maintained as it was at the time of forming, and it was processed smoothly while applying sufficient tension. I was able to do that.

Comparative Example 1 2.0 parts of magnesium oxide, 2 parts of t-butyl perbenzoate,
An unsaturated polyester resin compound consisting of 40 parts of calcium carbonate and 40 parts of calcium carbonate was thoroughly stirred and placed in a resin bath.

The same operation as in Example was repeated except that this resin compound was used instead, and the product was aged, and this aging took about 30 minutes.

Thereafter, the powder adhesion treatment was carried out in the same manner as in the example, and the obtained prepreg glovings were noticeably sticky and stuck to each other when wound onto a bobbin.

In addition, since this material lacks elasticity, even though it is manufactured with a circular cross-sectional shape, it flattens when wound onto a bobbin, which is combined with the above-mentioned stickiness. This caused significant problems in rewinding.

In this example, we tried increasing the ripening temperature to 110°C, but there was still no effect of shortening the ripening time, and there was no significant difference in the physical properties of the pre-pregloving itself.

Comparative Example 2 "Polylite PS-202" (product of the same company; solvent = methyl ethyl ketone) was selected as a diallylphthalate type unsaturated polyester resin, and 2 parts of t-butyl perbenzoate were kneaded with 100 parts of this. The same procedure as in Example was carried out except that the obtained resin compound was used instead and the solvent was almost completely volatilized in a heating furnace for 7 minutes. Because it was extremely sticky and had no elasticity, the cross-sectional shape became flat when it was wound onto a bobbin, and this together with this stickiness caused problems in unwinding.

In particular, after just a few days of being left alone, it became impossible to unwind, as they had become integrated rather than stuck together.

Also, as long as you follow the solvent type method as in this example,
Because the prepreg is formed by volatilization of the solvent, the furnace is constantly filled with solvent odor, which requires a separate device to treat it.

[Brief explanation of the drawing]

The drawing is a flow sheet showing one embodiment of the method of the present invention, and in the drawing, 1... Reinforcing material, 2... Resin tank, 3... Dice, 4... Heating device, 5... Separating device, 6...
Powder tank, 7... take-up device, 8... take-up device.

Claims (1)

[Scope of Claims] 1 () A step of impregnating a reinforcing material with an unsaturated polyester resin composition containing an unsaturated polyester resin composition containing an unsaturated polyester resin and a polyisocyanate compound as main components, () A step of controlling the amount of the resin composition impregnated into the reinforcing material and shaping the impregnated reinforcing material, and () passing the shaped impregnated material through a heating furnace. A method for manufacturing prepure gloving, which consists of a process of making it non-adhesive.