JPH0423812A - Alpha-olefin copolymer and its production - Google Patents

Abstract

PURPOSE:To obtain the subject copolymer useful as a compatibilizing agent having excellent miscibility and adhesion to polyolefin, etc., by copolymerizing alpha-olefin and an alicyclic epoxy group-containing unsaturated monomer using a radical polymerization catalyst. CONSTITUTION:(A) An alpha-olefin is copolymerized with (B) an unsaturated monomer having at least a species of alicyclic epoxy group [e.g. a compound expressed by the formula (R1 is H or methyl)] using a radical polymerization catalyst [preferably peroxide or azo compound expressed by the formula of X-O-O-Y type (X is aryl, alkyl or H; Y is X, etc.)] to afford the objective copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a novel α-olefin copolymer having an alicyclic epoxy group and a method for producing the same.

(Prior art) As an α-olefin copolymer having an epoxy group,
Monomers containing glycidyl groups, such as copolymers of glycidyl methacrylate and ethylene, are well known (UK Patent Section 1,146°579, Published Patent Application No. 1983-1999).
23490. Publication patent No. 48-11388).

These copolymers retain the excellent properties of polyethylene, such as processability, chemical resistance, and low-temperature embrittlement resistance, and have good compatibility with other resins, so they can be used with other polyolefins, polyamide resins, polyester resin, vinyl chloride resin,
Polycarbonate resin, AS resin, ABS resin, polystyrene resin, polyarylene ester resin, polyarylene sulfide resin, polyphenylene oxide resin, polyetherketone resin, polyetherimide resin,
It is used as a modifier for polyoxymethylene resins by blending them with them.

Furthermore, when blending incompatible resins, adding it as a compatibilizer increases the compatibility, making it possible to blend resins that are otherwise difficult to blend.

As a result, various polymer alloys have been developed.

It is also widely practiced to utilize the reactivity of epoxy groups in copolymers to introduce various functional groups by reacting resins and compounds with various active hydrogens.

(Problems to be Solved by the Invention) However, despite such usefulness, conventional ethylene copolymers having glycidyl groups have various problems because their epoxy groups are unstable at high temperatures. was there.

First, when producing this copolymer, when an α-olefin compound and glycidyl methacrylate are radically polymerized at high temperature, the glycidyl group is cleaved at the reaction temperature, and the resulting copolymer contains epoxy groups. There were problems such as a significant decrease in the amount of copolymer, and in some cases crosslinking reaction occurred due to decomposition, resulting in an increase in the melt viscosity of the copolymer.

Therefore, in order to avoid such problems, it has been impossible to increase the content of the glycidyl group-containing monomer in the copolymer, and copolymerization has been possible only below a limited proportion.

Moreover, if the polymerization temperature in copolymerization is also high, decomposition or cleavage of the epoxy group will occur, so copolymerization is also carried out while keeping the polymerization temperature below a certain temperature.

However, in such cases, the molecular weight of the copolymer increases and the melt viscosity of the copolymer itself increases, which not only makes the polymerization operation difficult but also causes problems such as poor blending characteristics with other resins. there were.

In addition, when blending with other resins using an extruder, etc., if the cross-mixing temperature is increased or the cross-mixing time is increased in order to achieve sufficient blending, the epoxy groups in the copolymer themselves may decompose or become self-contained. There were problems such as cleavage, resulting in significant coloring of the blended resin and failure to obtain the original blending effect. As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have discovered that a copolymer of an unsaturated monomer having an alicyclic epoxy group and an α-olefin compound has excellent thermal stability. We have discovered this and have arrived at the present invention.

(Structure of the Invention) That is, the present invention provides the following steps: ``obtained copolymer'' and ``(a) an α-olefin and (b) an unsaturated monomer having one or more types of alicyclic epoxy groups are copolymerized using a radical polymerization catalyst. ``Method for producing α-olefin copolymer''.

Examples of the α-olefin compound used in the present invention include ethylene and propylene, but α-olefins with larger molecular weights can also be used, and one type or a mixture of one or more types may be used.

The unsaturated monomer having an alicyclic epoxy group used in the present invention has one unsaturated bond copolymerizable with an α-olefin monomer in one molecule, and one or more alicyclic epoxy groups. It is a monomer with

For example, such monomers include those shown below. (Left below) ■ CH2 C-C-0 Key (n) Ro ■ CH2-C (V) CH2-C-C R8 CH2-C C-〇 - (VI) CH2 C R.

CH, -C N□ punishment CH.

-〇-N [In each general formula, R1 is a hydrogen atom or a methyl group, R2 is a divalent aliphatic saturated hydrocarbon group having 1 to 6 carbon atoms, and R3 is a divalent hydrocarbon group having 1 to 10 carbon atoms. Examples include things like:

However, an unsaturated monomer having a glycidyl group, such as glycidyl methacrylate, can also be used in combination with an unsaturated monomer having an alicyclic epoxy group within a range that does not impair the characteristics of the present invention. Among (I) to (X1), these are particularly easily available.

for example CH.

(m) is industrially and by Daicel Chemical Industries, Ltd. METHB and A
It has been commercialized as ETHB.

The radical polymerization catalyst used in the present invention generates radicals under polymerization conditions to cause a radical polymerization reaction of unsaturated monomers. It includes compounds that have.

Oxygen, hydrogen peroxide, organic peroxides, azo compounds, and the like are effective as such catalysts.

Among them, the general formula % formula % (wherein X is an oryl group, a derivative group thereof, an alkyl group,
Particularly effective are peroxides and azo compounds such as hydrogen, where X and Y may be the same or different.

In producing the polymer of the present invention, the reaction temperature is 40
~250°C.

At temperatures above 250°C, some cleavage of epoxy groups occurs and the content of epoxy groups in the copolymer decreases.

If the polymerization temperature is below 40° C., the polymerization reaction rate becomes extremely slow and a large amount of catalyst is required, which is industrially disadvantageous.

The copolymerization reaction can be carried out without using a solvent, but it can also be carried out in the coexistence of an inert solvent such as ethane, propane, butane, heptane, hexane, etc. Copolymerization can also be carried out to make small amounts of propylene, butene-1, isobutyne, and other α-olefins present.

The reaction may be carried out either batchwise or continuously, but it goes without saying that a reaction vessel capable of withstanding high pressure is required.

(Effects of the Invention) The α-olefin copolymer having an alicyclic epoxy group obtained by the present invention has good compatibility with polyolefins, and can be blended with other polyolefins to produce useful polyolefin compositions. can be provided.

In addition, it has high adhesion to metals such as iron and aluminum, cellophane, paper, etc., so it can be used for laminates, bonded products, laminates, etc.

Furthermore, the α-olefin copolymer can be used to produce reinforced polyolefin compositions with improved mechanical strength, dimensional stability, heat resistance, cold resistance, etc. by adding fillers such as polyolefin and glass fiber or glass powder. Can be used.

Furthermore, it can also be used as a compatibilizer by adding it to many thermoplastic resins for molding, such as polyester resins, polycarbonate resins, polyphenylene oxide resins, polystyrene resins, and polyamide resins, as well as polymer alloys made by blending two or more of them. can.

It can also be added to various composites made by mixing these polymer alloys with glass fibers, carbon fibers, glass powder, glass hollow particles, etc.

In particular, the epoxy group of the α-olefin copolymer having an alicyclic epoxy group of the present invention has excellent thermal stability, so the epoxy group will not be damaged especially under high temperature and long-term cross-wire conditions. Therefore, sufficient mixing of polymer blends and fillers is possible, resulting in excellent polymer compositions.

The α-olefin copolymer of the present invention is an antioxidant, a stabilizer, an antistatic agent, an ultraviolet absorber, an antiblocking agent,
Conventional additives and modifiers useful in conventional resin and plastics technology can be included, such as lubricants, pigments, colorants, etc.

EXAMPLES The present invention will be specifically explained below using examples.

However, the present invention is not limited to these in any way.

EXAMPLE In a 100 ml stainless steel autoclave equipped with a stirrer, 5 mg of cabrylyl peroxide and ME were added after repeated purging with oxygen-free ethylene.
2 g of THB [a methacrylic acid ester having an alicyclic epoxy group, a product of Daicel Chemical Industries, Ltd., structural formula % formula %] and 8 g of propane as a solvent were charged. Thereafter, ethylene was introduced to an appropriate pressure, the internal stirrer was started, and the reaction was started at 190° C. and a pressure of 1300 kg/cm 2 using an oil bath in the container.

When the pressure dropped to 800 kg/cm' after 120 minutes, the container was cooled and the pressure was released to obtain 4 g of a copolymer of ethylene and METHB.

The infrared absorption spectrum of this copolymer showed absorption at 1150 cm-2, which is characteristic of alicyclic epoxy groups, and absorption at 2900 cm-2, which is characteristic of polyethylene.

Further, from the results obtained from an infrared absorption spectrum calibration curve prepared based on elemental analysis and characteristic absorption of epoxy groups, it was found that METHB was contained in an amount of 30% by weight.

Further, when the oxirane oxygen content was measured by chemical analysis, it showed almost the theoretical value, and no cleavage of the epoxy group occurred during the polymerization reaction.

Comparative Example An epoxy group-containing copolymer was obtained by carrying out the same reaction as in Example, replacing MET'HB with glycidyl methacrylate.

When the epoxy group concentration of the copolymer was measured, 5% of the epoxy groups had disappeared.

Claims (2)

[Claims] (1) A copolymer obtained by copolymerizing (a) an α-olefin and (b) an unsaturated monomer having one or more alicyclic epoxy groups using a radical polymerization catalyst. (2) An α-olefin copolymer characterized by copolymerizing (a) an α-olefin and (b) an unsaturated monomer having one or more alicyclic epoxy groups using a radical polymerization catalyst. Method of manufacturing coalescence.