JPS5817496B2 - FRP - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for pre-treating the composite interface of a heat-resistant polyvinyl chloride molded product to enable composite with an FRP (glass fiber reinforced polyester resin) layer.

In recent years, equipment or devices in the chemical industry and the like have tended to become larger and have higher temperatures.

In response to this trend, there are already composite materials of general polyvinyl chloride moldings and FRP layers, but heat-resistant polyvinyl chloride moldings are also corrosion-resistant materials that can withstand use at higher temperatures than polyvinyl chloride moldings. A composite material of (post-chlorinated vinyl chloride molded product) and an FRP layer is desired.

However, compositing a heat-resistant polyvinyl chloride molding and an FRP layer is not as easy as compositing a general polyvinyl chloride molding and an FRP layer, and currently, compositing is extremely difficult or requires special treatment. I need.

This is because, in the case of general polyvinyl chloride molded products, the composite interface of the polyvinyl chloride molded product is primed with a backing resin containing a hardening agent, the composite interface is embedded with glass cloth, or the composite interface is sanded. By laminating a glass mat with an unsaturated polyester resin containing a hardening agent to each treated material, a composite material of a polyvinyl chloride molded product and an FRP layer with strong adhesive strength can be obtained. This is because, in the case of a heat-resistant polyvinyl chloride molded product, even if an FRP layer is composited by the above method, the curing of the backing resin or unsaturated polyester resin is extremely slow and sufficient adhesive strength cannot be obtained.

In the process of researching the composite of a heat-resistant polyvinyl chloride molded product and an FRP layer, the present inventor discovered that the antioxidant contained in the heat-resistant polyvinyl chloride molded product was an unsaturated polyester resin containing a curing agent or a backing resin. The present invention was developed based on the discovery that the antioxidant inhibits the curing of the heat-resistant polyvinyl chloride molded material, which is exposed at the composite interface of the heat-resistant polyvinyl chloride molded product before being composited with the FRP layer. This invention relates to a pretreatment method capable of providing a heat-resistant polyvinyl chloride molded product that can be combined with an FRP layer by removing the agent by the action of hydrochloric acid or acetic acid to improve the chemical affinity of the composite interface between the two. .

The antioxidant contained in the heat-resistant polyvinyl chloride molded product is also called an antioxidant, and for example, 2゜6-T-
Butyl-p-cresol (also known as 2゜6-sheet t-butyl-hydroxy-toluene, hereinafter referred to as B I- (abbreviated as T)
, n-octadecyl-β(4-
Hydroxy-3,5-di-t-butylphenyl)propionate, 2,2'-methylenebis(4-methyl-6-
t--j thylphenol), 4,4'-methylenebis(
2,6-di-t-butyl-phenol), 4,4'-
Butylidene bis(3-methyl-6-t-butylphenol) 4,4''-thiobis(3-methyl-6-1-butylphenol) and the like are well-known, and these antioxidants are used in heat-resistant polyvinyl chloride moldings. It is particularly preferred for use in molding.

This is because post-chlorinated vinyl chloride resin is processed at high temperatures, so it has poor thermal stability and is easily decomposed than general vinyl chloride resin, so lead-based stabilizers (tribase, neobase, etc.) or tin-based It is used as a stabilizer (such as a tin malate compound) or as a main stabilizer, and is used in conjunction with an antioxidant, and is usually used in an amount of about 0.5 parts by weight per 100 parts by weight of post-chlorinated vinyl chloride resin. The thermoplastic polyvinyl chloride molded product contains the above-mentioned antioxidant.

On the other hand, when a heat-resistant polyvinyl chloride molded product and an FRP layer are integrated into a composite, an unsaturated polyester resin containing a curing agent is used, or a more effective adhesive is applied to the composite interface of the heat-resistant polyvinyl chloride molded product before composite formation. A backing resin containing a hardening agent is used as a primer treatment for hardening.

Typical examples of this curing agent include peroxides such as methyl ethyl ketone peroxide (hereinafter abbreviated as MEKPO) and benzoyl peroxide (hereinafter abbreviated as BPO), and are usually used in an amount of about 1 to 3% by weight. ing.

By the way, the action of the curing agent contained in these unsaturated polyester resins or backing resins is inhibited by the antioxidant in the heat-resistant polyvinyl chloride molding, and the curing agent is not fully cured, resulting in a sticky phenomenon observed on the adhesive surface. Either the vinyl chloride molded product and the FRP layer cannot be integrated at all, or even if they can be integrated, the curing time is extremely long (
(Requires 3 hours or more) Workability is poor.

By the way, is it okay to accelerate curing by increasing the amount of curing agent?In the actual construction of large equipment such as tanks and ducts, if the curing speed is too fast, it may be difficult to work. It is unreasonable, and in actual construction work, 6
In many cases, the compound is transferred within ~12 hours, so
During this time, it is necessary that the unsaturated polyester resin has already been completely cured.

Therefore, the present invention attempts to remove the antioxidant exposed at the composite interface with the FRP layer of the heat-resistant polyvinyl chloride molded product using acid before composite and cure it in a short time. Use hydrochloric acid or acetic acid as a removing agent.

By the way, if you want to simply remove the antioxidant from a heat-resistant polyvinyl chloride molded article, you can use ethyl acetate, acetone, an extractant for the antioxidant, in addition to the method of removing the antioxidant using hydrochloric acid or acetic acid. Although a method of extracting and removing the antioxidant using an organic solvent such as methanol has been considered, it has been found that this extraction and removal method cannot achieve the object of the present invention.

Therefore, although the present invention uses hydrochloric acid or acetic acid to remove antioxidants, acetic acid has a better removal effect than hydrochloric acid even at a lower concentration and is also safer to handle.

As a treatment method for removing the antioxidant, the composite interface of the heat-resistant polyvinyl chloride molded product may be wiped with a cloth soaked in hydrochloric acid or acetic acid, or the entire heat-resistant polyvinyl chloride molded product may be wiped with a hydrochloric acid or acetic acid solution. It may also be immersed in the liquid.

Next, the heat-resistant polyvinyl chloride molded product, which has been pretreated to remove the antioxidant with hydrochloric acid or acetic acid, is subjected to composite integration with an FRP layer, and the composite is carried out in the usual manner.

It should be noted that the method of compositing, except for pretreatment, is the same as in the case of a general polyvinyl chloride molded product and an FRP layer.

Composite method 1: After pre-treating the composite interface of the heat-resistant polyvinyl chloride molding, apply a packing roller containing a hardening agent with a coating roller, and after curing, unsaturated polyester resin containing a hardening agent. A method of combining the FRP layer by applying glass mat to the required thickness using a coating roller and degassing roller.

Composite method 2: half of the crow cloth on the composite interface? After pre-treating the composite interface of the embedded heat-resistant polyvinyl chloride molding, a glass mat is attached to the required thickness using an unsaturated polyester resin containing a hardening agent, and an I" RP layer is composited.

Composite method 3: After pre-treating the composite interface of the heat-resistant polyvinyl chloride molded product that has been subjected to sandin-mig treatment with a sand vapor, a glass mat of the required thickness is attached using an unsaturated polyester resin that also contains a hardening agent, and an FRP layer is composited. how to.

Experiments and examples are described below.

The composite interface of a ml thermal polyhinyl chloride molded product [HT925, manufactured by Takiron Sou 0] containing an antioxidant (BHT) was pretreated with or without pretreatment using various concentrations of hydrochloric acid or acetic acid, respectively. Glass mats were laminated using unsaturated polyester resins with varying concentrations of curing agent (MEKPO), and the cured state of the heat-resistant polyvinyl chloride molded product and the FRP layer was measured.

The results are shown in Table -F. From the above facts and experiments, it has been found that when the composite interface of a heat-resistant polyvinyl chloride molded product containing an antioxidant is not pretreated, the adhesive phenomenon does not occur even after 6 days when the concentration of the curing agent in the unsaturated polyester resin is 1%. As can be seen, when the concentration of the hardening agent was increased to 2%, it was only slightly hardened after 3 days.

On the other hand, when pre-treated with hydrochloric acid or acetic acid, it cured in a shorter time than without treatment (some cases were completely cured after 6 hours), and the higher the concentration of hydrochloric acid and acetic acid, the more It can also be seen that the higher the concentration of the curing agent, the shorter the curing time, and that the curing time is shorter with acetic acid than with hydrochloric acid even if the concentration is lower.

Example 1 10% composite interface of heat-resistant polyvinyl chloride molded product CHT925 (manufactured by Takiron Co., Ltd.) containing an antioxidant (BHT')
After treatment with acetic acid and complete drying, hardening agent (MEKPO
) 1% of the backing resin [Takihondo #900, manufactured by Takiron ■] was coated and treated with a brimer, and after the backing resin was almost cured, a curing agent (MEKPO) of 2% was applied.
The second layer of glass mat is laminated using an unsaturated polyester resin containing
Laminated using unsaturated polyester resin containing 1%,
A composite material of a heat-resistant polyvinyl chloride molded product and an FRP layer was obtained.

In this composite material, both the backing resin and the unsaturated polyester resin were completely cured and firmly adhered to each other after 6 hours had passed since the composite material was formed.

On the other hand, without pre-treating the composite interface of the heat-resistant polyvinyl chloride molded product with acetic acid, FR was prepared in the same manner as above.
P layer was laminated, but heat-resistant polyvinyl chloride molded product and FRP
An adhesion phenomenon was observed on the adhesive surface with the layer, and it was easily peeled off without curing even after 6 days had passed.

Example 2 The composite interface of a heat-resistant polyvinyl chloride molded CFR plate containing an antioxidant (BHT) with glass cloth half embedded in the composite interface side, manufactured by Takiron ■ was treated with 20% hydrochloric acid and completely dried. After that, the glass mat is laminated using unsaturated polyester resin containing 2% hardening agent (MEKPO).
When this process was carried out, a completely cured composite material of the heat-resistant polyvinyl chloride molded product and the FRP layer was obtained after 6 hours.

On the other hand, when FRP layers were laminated in the same manner without pre-treating the composite interface of the heat-resistant polyvinyl chloride molded product with hydrochloric acid, a sticky phenomenon was observed on the adhesive surface and it remained uncured even after 2 days. there were.

Example 3 Antioxidant (4,4'-butylidenebis(3-methyl-6
After sanding the composite interface of a heat-resistant polyvinyl chloride molded product (FR plate, manufactured by Takiron ■) containing (-t-butylphenol) with sandpaper, the sanded composite interface was treated with 10% acetic acid to completely remove the After drying,
One layer of glass mat is laminated using unsaturated polyester resin containing 2% hardening agent (BPO), and the second layer is laminated with unsaturated polyester resin containing 1% hardening agent (BPO), heat-resistant polychloride. A composite material of a vinyl molded product and an FRP layer was obtained.

This composite agent was completely cured and bonded 6 hours after the composite was formed.

On the other hand, when FRP layers are laminated in the same manner without treating the sanded composite interface with acetic acid,
Even after 2 days had elapsed, a sticky phenomenon was still observed on the adhesive surface.

I believe that you have already understood the present invention from the above explanations, experiments, and examples. On the other hand, the present invention performs a simple pretreatment of removing the antioxidant exposed at the composite interface of the molded product with hydrochloric acid or acetic acid before composite with the FRP layer. The composite integration of a heat-resistant polyvinyl chloride molded product and an FRP layer, which required processing, can be completed in a short time using the usual composite method used for composite integration of a general polyvinyl chloride molded product and an FRP layer. It has been possible to provide a heat-resistant polyvinyl chloride molded product for composite use with an FRP layer, which can be composited, and is useful as a material for use in equipment and devices in the chemical industry that tend to be larger and have higher temperatures.

Claims (1)

[Claims] 1 Heat-resistant polyvinyl chloride molded product containing antioxidant and FRP
In the method of forming a composite and integral layer with the FRP layer, the antioxidant is removed by treating the composite interface of the heat-resistant polyvinyl chloride molded product with hydrochloric acid or acetic acid before this composite. A pretreatment method for heat-resistant polyvinyl chloride molded products that can be combined with