JPS62184046A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin compsn. having excellent flame retardance, heat resistance and adhesion and suitable for use as a hot-melt adhesive in particular, by blending a specified vinyl chloride/vinylidene chloride copolymer with a phenolic resin. CONSTITUTION:A resin compsn. consists of a copolymer having a number- average MW of 4,000-20,000 obtd. by copolymerizing a monomer mixture of vinyl chloride, vinylidene chloride and other copolymerizable monomers and a phenolic resin. When the number-average MW of the copolymer is less than 4,000, the heat resistance, mechanical strength and bond strength are lowered, while when it exceeds 20,000, the compatibility thereof with the phenolic resin is lowered. The ratio of vinyl chloride to vinylidene chloride is pref. 10-90:90-10(wt%). Among the compositions having the above ratio, those comprising a chlorine-contg. copolymer having a m.p. of 70-100 deg.C are particularly preferred.

Description

Detailed Description of the Invention (a) Object of the Invention [Field of Industrial Application] The present invention relates to a resin composition comprising a vinyl chloride/vinylidene chloride copolymer and a phenol resin, and the present invention relates to a resin composition of the present invention. The product is particularly used as a hot-melt adhesive necessary for manufacturing felts, laminates, resinoid grindstones, etc.

[Prior art and intervening points]

Vinyl chloride/vinylidene chloride-based comonomers are inexpensive raw materials and have excellent flame retardancy, so they are partially used as hot-melt (W) adhesives.

However, in general, the balance between melt fluidity and heat resistance is poor (if you try to provide melt fluidity below 180°C, the softening temperature will be below 100°C, and in application fields where heat resistance is required, I've been restricted.

As a method to improve this point, a monomer that provides a crosslinked structure at high temperatures, such as a monomer having an epoxy group or a hydroxyl group such as glycidyl methacrylate, hydroxyethyl acrylate, or hydroxypropyl acrylate, and maleic anhydride, hymic anhydride, or acrylic anhydride. Although copolymers with acid anhydrides or carboxylic acids have been proposed, no significant improvements have been made so far.

Furthermore, the vinyl chloride/vinylidene chloride copolymer is soluble M! II Since the flow temperature and the thermal decomposition temperature are close,
It is unavoidable that a small amount of hydrochloric acid is released during heating, and for this reason, there has been concern about corrosion of the bonding heating device or the metal fittings of the bonded molded product.

On the other hand, phenolic resin is particularly cheap, so it is used in felt,
Widely used as a binder for laminates or abrasive materials.

However, since the adhesive strength is small relative to the amount of resin used, it is not suitable for producing felts made of cotton or cotton/Tetoron blend yarns that have a soft texture. However, it is also prone to brittleness and has drawbacks in terms of bending strength or impact strength, making it difficult to use, especially for heavy-duty grinding wheels.

(B) Structure of the Invention [Means for Solving the Problems] The present inventors have completed the present invention as a result of studying the above-mentioned problems.

That is, the present invention provides a copolymer having a number average molecular cap of 4,000 to 20,000 (hereinafter referred to as It is a resin composition consisting of a chlorine-based copolymer) and a phenolic resin.

[Chlorine-based copolymer]

The chlorinated copolymer used in the present invention is a copolymer of vinyl chloride and vinylidene chloride, or a copolymer of vinyl chloride, vinylidene chloride, and a monomer copolymerizable with these, and has a number average molecular weight of 4,000 to 4,000. 20,000.

The ratio of vinyl chloride and vinylidene chloride used is preferably 10 to 90 fin% vinyl chloride and 10 to 90 fin% vinyl chloride, and among those obtained within this range,
Particularly preferred is a chlorine copolymer having a melting point of 70 to 100°C.

If the proportion of vinyl chloride is less than 10g or the proportion of vinylidene chloride exceeds 90% by weight, the melt fluidity and adhesion will be poor (easily), and if the proportion of vinyl chloride exceeds 90% by weight or the proportion of vinylidene chloride exceeds 90% by weight. If the melting point of the chlorine-based copolymer is less than 70°C, the heat resistance tends to decrease, and if it exceeds 100°C, the adhesiveness tends to decrease. tends to decrease.

Other copolymerizable monomers include, for example, allyl chloride, methallyl chloride, allyl acetate, vinyl ester, vinyl ether, acrylic ester, vinyl ketone, acrylic acid, hydroxylethyl acrylate, maleic anhydride, N-methylacrylamide, meth Lilsulfonic acid sodium and glycidyl methacrylate are often used.

The proportion of this copolymerizable monomer used is 20J1 in all monomers.
It is preferable that it is less than f-jit.

By combining the above monomers using a conventional suspension method, emulsification method, etc., a chlorine-based co-summerized product can be easily obtained.

The obtained chlorine-based copolymer has extremely high fluidity.

The number average molecular cap of chlorine-based copolymer is 4U00-20000
It is necessary that it is, and it is preferable that it is 5000-17000. If the number average molecular weight is less than 4,000, heat resistance, mechanical strength, and adhesive strength will decrease;
If the amount exceeds 100%, the compatibility with the phenolic resin decreases.

The number average molecular weight as used in the present invention is a polystyrene equivalent molecular weight measured by gel permeator chromatography (hereinafter referred to as GPC). - The measurement conditions by GPC are as follows.

Equipment 1f: High performance liquid chromatography (e.g. Toyo Soda Kogyo ■ Part name HLC-801A) Column: Polystyrene gel (e.g. Toyo III Datsu Kogyo ■ ILi! Product name C7M1"l) Bathing solvent: Tetrahydrofuran outflow? Degree: 1-01 RI/m Pressure Crab 15k)/cd Column temperature: 40°C Furthermore, the particle size of the chlorine-based copolymer is preferably 200 mesh or less, and if the particle size is larger than 200 mesh, it may be difficult to mix with the phenol resin. The properties tend to deteriorate, and the adhesion tends to decrease as well.

[Phenol resin]

The phenol resin used in the present invention may be either a novolac type or a resol type, but the novolac type is suitable for use as a hot melt adhesive.

Novolac type phenolic resin is obtained by reacting phenol and formaldehyde under an acidic catalyst. The ratio of phenol and formaldehyde used is preferably 0.7 to 0.9 mol of formaldehyde per 1 mol of phenol.

Furthermore, in order to carry out a crosslinking reaction, 8 to 10 parts of hexamethylenetetramine as a curing agent is added to 100 parts by weight of the phenol resin.
Parts by weight can be added.

The particle size of the phenol resin is preferably a fine powder with a particle size of 200 mesh or less in terms of miscibility with the chlorine-based copolymer.

[Resin composition]

The resin composition of the present invention is a mixture of the above-mentioned chlorine co-monomer and phenol resin, and the mixing ratio is 20 to 80% by weight of the chlorine comonomer and 80 to 20'N of phenolic resin.
Quantity is preferred. If the chlorine-based copolymer is less than 20iii% or the phenolic resin is more than 80%, the adhesion, II flammability, and bending strength tend to decrease, and the odor of the phenolic resin remains. , chlorine copolymer is 80
If the amount of phenolic resin exceeds 20I, the balance between melt fluidity and heat resistance will be poor (
It is easily thermally decomposed during bonding and heating.

The method of mixing chlorine copolymer and phenolic resin is 200
A method of tri-blending both resins in the form of fine powders of mesh size or smaller is simple and preferred.

〔Example〕

EXAMPLES The present invention will be explained in more detail below with reference to Examples and Comparative Examples. In addition, physical property evaluation in 6 examples followed the following method.

1) Normal peel strength and heat-resistant peel strength Polymer particles were uniformly scattered on a blended fiber sheet of polyester/cotton (65735 weight ratio) to a thickness of 201//m, and the same sheet was placed on top of this and heated at 170°C. x O,
After press bonding was carried out under conditions of 3kp/a/lx for 10 seconds, the peel strengths at 25°C and 80°C were measured.

2) Residual odor The test piece obtained in 1) after peel strength measurement was left at room temperature for 24 hours, and the residual odor of the attached polymer was observed by smell.

3) Pyrolytic decomposition The polymer powder was placed on a smooth iron plate, held at 170°C, and the time until it turned black was measured.

4) Number average molecular weight of chlorine-based copolymer Measured by GPC, and the molecular weight in terms of polystyrene was used for 3 bales.

Example 1 Vinylidene chloride 7E 4% by weight and vinyl chloride 25TLIr,
Polymerizing a monomer mixture consisting of % by suspension polymerization method,
A chlorine-based comonomer having a number average molecular weight of 11,000 and a passing t of 971 (tJ) due to the mesh size of 200 was obtained.

On the other hand, 1 mole of phenol and 0.8 mole of formaldehyde were reacted at 100°C for 3 hours using hydrochloric acid as a catalyst, and 1011 (i%) of hexamethylenetetramine was added, passing through 200 meshes at a melting point of 85°C. A novolak type phenol and resin was obtained.

A resin composition was obtained by mixing 80:1 fIk part of the above chlorine-based copolymer and 20 parts by weight of the phenol resin in a dry blender for 30 minutes.

The physical property evaluation results of this resin composition are shown in Table 1.O Examples 2 to 8 and Comparative Examples 1 to 4 Same as Example 1 except that the types and blending ratios of the chlorine copolymer and phenol resin were changed. A resin composition was obtained.

Table 1 shows the results of evaluating the physical properties of the resin composition.

(c) Effects of the Invention The resin composition of the present invention has excellent flame retardancy, heat resistance, and adhesive properties, has no residual odor, and can be processed at low temperatures, so it is particularly suitable for hot melt adhesives. It is industrially useful as

patent issuer Toagosei Chemical Industry Co., Ltd.

Claims (1)

[Claims] 1. A resin consisting of a copolymer having a number average molecular weight of 4,000 to 20,000, obtained by copolymerizing vinyl chloride, vinylidene chloride, or a monomer mixture of these and other copolymerizable monomers, and a phenol resin. Composition.