JPH03181581A - Adhesion between polyvinylidene fluoride molding and general-purpose resin - Google Patents

Abstract

PURPOSE:To readily bond adherent materials consisting of different kinds of polymer materials using the hot-melt adhesion method by using a mixture composed of polymethyl methacrylate resin and polyvinylidene fluoride resin in a specified ratio as an adhesive. CONSTITUTION:Using a resin composition obtained by blending (A) 15-90vol.% polymethyl methacrylate rosin with (B) polyvinylidene fluoride resin as an adhesive, adhesion between both the adherent materials composed of a polyvinylidene fluoride resin as one adherent material and a rigid polyvinyl chloride molding or a polystyrene molding as the other adherent material is carried out by heating and fusing the adhesive preferably at a temperature within a range of 220-240 deg.C and subsequently letting it stand to cool.

Description

[Detailed description of the invention] (a) Industrial field of use Provides a means for connecting wiring and piping in cities, buildings, equipment, etc., assembling building parts, interior appliances, miscellaneous goods, manufacturing laminated panels, etc. This will expand the fields of use for general-purpose resins.

(b) Conventional technology Polyvinylidene fluoride resin (hereinafter referred to as PVDF)
is known as a material that has excellent chemical resistance, weather resistance, and electrical properties, but it is difficult to bond with different types of polymer materials, and adhesives that can provide adhesive strength that can be used for practical purposes have yet to be developed. This is adhesion with polyethylene resin using a mixed resin of PVDF and polyethylene, etc., as described in Application No. 6317290. Practically usable adhesives and bonding methods for bonding polystyrene molded articles and hard vinyl chloride molded articles are hardly known.

<C> Problems to be solved by the invention Hard vinyl chloride molded products (10% plasticizer according to Japanese Industrial Standards)
It is defined as the following polyvinyl chloride resin.
Hereinafter, it will be referred to as pvch. > Alternatively, by easily bonding polystyrene (hereinafter referred to as PS) and PVDF molded products, and forming a PVDF coating layer on the surface of the PVCH or PS molded products, the chemical resistance and weather resistance of the surfaces of these molded products can be improved. improve properties or impart electrical properties.

(d) Means for solving the problem Let the adherend material PVDF be A, and the adherend material pvch or PS
Let B be an adhesive to bond A and B, and A
We have discovered a method of bonding B and B by heat fusion.

The adhesive used in the present invention is PVDF and polymethyl methacrylate resin (hereinafter referred to as PMMA).

) is a mixed resin.

Next, each component of the adhesive resin composition of the present invention will be explained. pVDF in the present invention is a polymer of vinylidene fluoride monomer and has the following molecular structure.

(-CH2-CF2- C1l□-CF2-), l As PVDF having the above molecular structure, injection molding, extrusion molding grade, etc. can be used.
In Japan, F is produced and sold under the trade names such as "rKF Polymer" by Kureha Chemical Industries, Ltd. and "Neoflon VDF" by Daikin Industries, Ltd.

Other targets include polymers whose main component is vinylidene fluoride monomer.

PMMA is a polymer of methyl methacrylate.In Japan, products such as plates, rods, and pipes formed by polymerization are commercially available, but the polymer is manufactured by Mitsubishi Rayon Co., Ltd.'s ``Acrivet'' as a raw material for injection molding. It is manufactured and sold under the trade name.

Extrusion equipment, twin-screw rollers, etc. are used to mix resins for the production of adhesives. Mixing temperature is PVDF, PM
The temperature is within a range where both MA melts and does not undergo thermal deterioration, and is usually preferably around 200°C.

The adherend materials PS and PVCH are molded products whose main components are these resins.

In the present invention, the mixing ratio of resins is defined as follows.

PMMA resin mixing ratio (%) = 1.00 x PM
MA volume/(PMMA + PVDF) volume The volume is the true volume. If filler is present, the filler component is excluded from this mixing ratio calculation.

Bonding is completed by bringing the adhesive and the adherend into contact with each other in a molten state at the bonding location, applying pressure with a slight force, and cooling the adherend while maintaining the fused state. The heating temperature range at this time should be above the melting temperature of each resin and below the temperature at which thermal deterioration is not severe, but in reality it is 220 to 24
0°C is preferred.

The relationship between the PMMA mixing ratio of the adhesive and the adhesive force (tensile force) is shown in the example, but from the viewpoint of adhesive strength, the range of this mixing ratio is
The A resin mixing ratio is 15% or more, and even when the adherend is PVDF and PS, 15% or more is the practical adhesion strength (here, 50%).
Although adhesion is possible even with an upper limit of 100%, as a result of actual measurements, it is close to the limit of practical adhesive strength, so in the present invention, the upper limit is set at 90%.

Although there is no known method for bonding PVDF and pvch or PS, the present invention has made it possible, and the reason for this will be explained below.

Generally, solubility parameters are used to interpret the mixing and dissolution phenomena of different types of organic molecules; mixing and dissolving substances with parameter values close to each other is easy, but it is difficult when they are far apart. .

This tendency is said to be more pronounced in polymers.

However, despite the difference in solubility parameters between PVDF and PMMA, it is known that these resins have good miscibility, and by applying this good miscibility, PVDF and PMMA are can also be easily attached.

Rod-shaped PVDF is shown as a reference figure in the example.
Simply touch the tip of PMMA with the tip of the PMMA in the air of an air burner controlled at around 220℃ and press lightly.
Both rods can be fused and bonded together.

Adhesion is also possible using a mixed resin of PVDF and PMMA as an adhesive, and as a result of measuring the adhesive force in a tensile test, a strong adhesive force of 200 kg/CII+2 was obtained in both cases. Figure 3 ) ps and pvch
It is impossible to heat-fuse and bond PVDF and PVDF without an adhesive. However, in terms of solubility parameters, ps, pvc
Polyvinyl chloride, which is the main component of cpvch, is referred to as PV below.
C> and PMMA are close to each other. Further, PMMA and PS or pvch can be thermally fused and bonded.

Applying the phenomenon of compatibility between PVDF and PMMA and the solubility parameter approximation between PMMA and PS or PVC, a mixed resin of PVDF and PMMA was prepared, used as an adhesive, and PVDF was applied to one side. It has been found that when one of the adherends is PS or PVC, it is possible to bond by heating, melting, and contacting at around 220°C. °Adhesion conditions, etc. are described in the examples, but the temperature range for adhesion is above the melting point or softening point of PVDF = PVC or PS, and below the temperature at which thermal deterioration of these resins is not severe. A common molding temperature range is preferred, but to reduce the time required for bonding,
Higher temperatures are also used for bonding.

Methyl methacrylate monomer and ethyl methacrylate, butyl methacrylate, or acrylic esters have similar chemical structures, and polymers of these monomers are compatible with each other. A copolymer of these monomers and methyl methacrylate or a copolymer of these monomers and PMMAt! A method of using a resin mixed with lubricant as a mature plastic solid and further mixed with PVDF as an adhesive can also be inferred from this patent.

As a result of experiments, it was found that adhesion was difficult when using soft vinyl chloride resin as the adherend material instead of PVC film, but it was possible to adhere PVC film. It also includes products mixed with fillers. Instead of PS, polystyrene graft copolymers, copolymers containing styrene monomers, copolymers of styrene and methyl methacrylate, and mixed resins containing these resins as main components may also be used as adherends. This can be inferred from the present invention.

KUBO> Function PVDF and PVCH or PS molded products can be bonded together. Also, since it is now possible to bond,
It becomes possible to form a PVDF layer coating on the surface of a PVCH or PS molded product.

PVDF has excellent water resistance, acid resistance, alkali resistance, etc., and by forming a PVDF layer on the surface of PVCH and PSS molded products, it is possible to improve the weather resistance, chemical resistance, etc. of these molded products.

(F) Example Adhesive, PVD as a resin that is a raw material for making an adherend
For F, KF Polymer from Kureha Chemical Industry Co., Ltd. was used.

As the adhesive raw material PMMA, Mitsubishi Rayon Co., Ltd.'s Acrybet was used.

PVDF as an adherend was formed into a flat plate with a thickness of 5 mm using a heat press, and a round bar with a diameter of 5 mm was cut from the flat plate.

A round bar with a diameter of 5+u+ was prepared by cutting a commercially available physical and chemical plate with a thickness of 5 mm for the pvch as an adherend.
The PS used was a round bar formed using an extrusion device using Asahi Dow Co., Ltd.'s Styron 666 pellets as a raw material.

A prototype Weisenberg resin mixing extrusion device (patent application No. 63-1952) was used to mix resins, etc. for making adhesives.
74 similar) was used. Since the volume of the gap space between the surface of the fixed body and the surface of the rotating body is approximately 10 cc, the raw material collection target is a true volume of polymer of 11i5 cc per container, and two containers can fill the gap space. Three containers were prepared as a standard. PVDF, PMM
The specific gravity of A is 1.76, 1. ．． 19, the weight of the raw material to be collected is determined by calculation from the resin mixing rate and filling rate that have been set, and the weight of the raw material is 1.
Collected in a container. At a temperature of 200° C. on the surface of the fixed body and on the surface of the rotating body, and at a rotation speed of 80 revolutions per minute, the raw materials were gradually fed from the container into the hopper with care so that they were uniformly mixed. In order to make the mixture uniform, the extrudate was extruded again and again, and the number of extrusions was 3 times as standard. The extruded resin is made into an appropriately sized lump and a heat press is used to bond two rods of different materials to a 0.3 mm thick sheet. Cut it out and use it as adhesive. Next, a thin polytetratonated ethylene sheet (used as a release material) is placed on a heated metal plate with a smooth surface whose surface temperature is controlled at around 220°C, and adhesive is placed on the sheet and one of the rods is placed on one side of the sheet. Weld the adhesive to the tip of the Next 210~
Using an air burner controlled at 240°C, heat the tip of the round bar bonded with the adhesive and the tip of another type of round bar together, and after confirming that the tips have melted together, remove the tip. Bring them into contact and press lightly to fuse them, then maintain that state and cool to complete the bonding.

In order to measure adhesive strength, the axes of the glued rods need to be on almost the same straight line, but if the length of the melted part at the tip is too long or the pressing force is too strong, the melted part will bend and the test will fail. It is not possible to make a test piece for this purpose, so some practice is required for gluing.

The adhesive strength was measured using a Tensilon UTM E model at a tensile speed of 4 vm/min, and the adhesive strength was determined by dividing the strength by the area of the fractured surface. In such tests, the adhesive surface is the weakest, and the adhesive can be treated as having no elongation.

There are cases where anisotropy occurs in the resin flow during adhesive preparation, and a circular adhesive changes into an elliptical shape during bonding, so the fracture surface area was calculated approximately as a circle or an ellipse. Since there are many variations in the data, out of the 5 samples that could be bonded,
The average value of the top three results is shown. The relationship between the measurement results of adhesive strength and the PMMA resin mixing ratio is shown in the figure. Figure 1 shows the case where the adherends are PVDF and PVCH molded products, and Figure 2 shows the case where the adherends are PVDF and PS molded products.
jU3 is a reference diagram that shows the relationship between the adhesive force and the PMMA resin mixing ratio when a round bar with a diameter of 5mm is bonded to a PMMA-coated village, a VDF-coated body, and a VDF-coated body using the same method as above. It is.

In both figures, the vertical axis is the tensile adhesive strength (Kg/cm"), the . on the graph is the actual measurement point, and the solid line is the line connecting the actual measurement points. The horizontal axis is the PMMAI!f fat mixture ratio - P old A/ (PMMA
+PVDF) is expressed in volume %.

(g) In addition to the effects of the invention, the adhesive method of the present invention has made it possible to bond a PVCH molded product or a PS molded product to a PVDF predetermined product.

PVDF has solvent resistance, acid resistance, alkali resistance, weather resistance,
Because it has excellent electrical insulation properties and has better heat resistance than PVCH, PVDF is suitable for fields that use PVCH and PS molded products, such as pipes, tubes, connector plates and sheets for these, etc. PVCh ps, which is inexpensive by combining carved pieces or forming a coating layer, etc.
It has become easier to add value to products.

[Brief explanation of drawings]

The figure is a graph showing the adhesive force measurement results when a mixed resin of PVDF and PMMA was used as the adhesive and different types of resins were used as adherends. The vertical axis is the tensile adhesive force, the unit is kilograms/square centimeter (Kg/cm ), and the ・ on the graph is the measurement point.
The solid line is a line connecting measurement points. The horizontal axis is the PMMA resin mixing ratio of the adhesive (PMMA / (P
VDF+PMMA )) Volume % information. Regarding the combinations of adherends, Fig. 1 shows PVDF-PVCh, Fig. 2 shows PVDF-PS, and Fig. 3 shows PVDF-PMMA. Figure 3 is shown as a reference diagram.

Claims (1)

[Claims] A resin composition consisting of a polymethyl methacrylate resin and a polyvinylidene fluoride resin is mixed so that the volume ratio of the polymethyl methacrylate resin is 15 to 90% is used as an adhesive, and one of the adherends is A method of bonding adherends made of different types of polymeric materials by using polyvinylidene fluoride resin, one adherend being a hard vinyl chloride molding or polystyrene molding, heating and fusing, and allowing to cool.