JPS60190405A - Acryl syrup composition - Google Patents

Abstract

PURPOSE:A composition that is composed of a polymer from, e.g., methyl methacrylate, a phosphine and a radical polymerization initiator, thus being satisfactorily curable even in the air atmosphere and showing its good characters in the application to large-sized adhesion and lamination. CONSTITUTION:The composition is composed of (A) partially polymerized substance of methyl methacrylate only or a mixture thereof with other monomers such as 1-18C alcohol acrylate ester or styrene, (B) a compound of R3X (R is 1-4C alkyl, substituted or unsubstituted phenyl; X is P, As, Sb) such as triphenyl phosphine, and (C) a radical polymerization initiator such as 2,2'-azobisisobutyronitrile, preferably in an amount of 5-50wt% A, 0.1-1pt.wt., per 100pts. wt. of the syrup, of B and 0.01-10pts.wt. of C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an acrylic syrup composition that is curable in an air atmosphere.

[Prior art]

Acrylic syrup, which is a partial polymer of methyl methacrylate alone or a monomer mixture containing methyl methacrylate as a main component, is used for casting, contact molding, lamination, etc. However, when methyl methacrylate is polymerized in an air atmosphere using an azo compound, an organic peroxide, etc., the polymerization is inhibited by the influence of oxygen in the air.

However, if the first step is performed in an air atmosphere, the first step of the air-contacting portion is delayed and the surface becomes soft. By leaving it for a long time, the monomer evaporates and hardens (However, products made in this state are likely to develop defects such as cranks during long-term use. Covering with polyester film, etc. is done. Although this method is technologically advanced, it is quite complicated in practical work, and it is necessary to remove the film and finish after curing. k) It is inferior in workability and productivity. In addition to the method of blocking air with a film, there is a method of curing in a nitrogen gas atmosphere, but this method requires special equipment and is not suitable for bonding or laminating large products.

[Purpose of the invention]

The present invention has been made in view of the prior art as described above, and it is an object of the present invention to provide an acrylic syrup composition that is sufficiently cured even in an air atmosphere.

[Structure of the invention]

The acrylic syrup composition of the present invention comprises A) a partial polymer of methyl methacrylate alone or a monomer mixture containing methyl methacrylate as a main component, B) a general formula R,X [II] (wherein R is carbon It is an alkyl group of number 1 to 4, or an unsubstituted or substituted tzenyl group, and X represents phosphorus, arsenic or antimony, and comprises a compound represented by 1°) and C) a radical polymerization initiator.

The partial polymer of methyl methacrylate or a monomer mixture containing methyl methacrylate as a main component (hereinafter referred to as ◆≠70 tube) used to constitute the composition of the present invention is:
It is prepared by partially polymerizing those monomers, or by dissolving the polymer in the monomers before forming the composition. Other copolymerizable monomers used to produce syrup include those having 1 to 18 carbon atoms;
ester of alcohol and acrylic acid, carbon number 2-1
Specific examples include esters of 8 alcohols and methacrylic acid, acrylic acid, methacrylic acid, cyclohexyl methacrylate, acrylonitrile, acrylamide and its derivatives, methacrylamide and its derivatives, styrene/and its derivatives, maninic anhydride, etc. I can give it to you. These monomers can be used alone or in combination of two or more, and their usage range is suitably within the commonly used range, that is, 19% by weight or less, but methacrylic acid alkyl ester or acrylic acid When an alkyl ester is used, VC can be used up to an amount of less than 60 weight plates of methyl methacrylate.

In the present invention, the concentration of monomer in the syrup used is preferably within the usual range, ie in the range of 5 to 50% by weight. If the weight ratio is less than 5, the curing property is poor, and 50
If the weight exceeds the weight, curing properties are good, but ordinary products only have poor physical properties.

Examples of the compound represented by the general formula [I] used in the present invention include trimenalphosphine, triethylphosphine, tripropylphosphine, triinpropylphosphine, tri-n-butylphosphine/, trise
e, -butylpho(5) Sufi/, triynebutylphosphine, triphenylphosphine, trivalatrylphosphine, triparachlorphenylphosphine, triparaphromophenylphosphine, trimethyl arsenic, triethyl arsenic, tripropyl arsenic, triisopropyl arsenic, tri-n-butyl arsenic, tri-1!lie, -butyl arsenic, tri-n-butyl arsenic, triphenyl arsenic, trimethyl antimono,
Examples include triethyl antimony/, tripropylene/antimony, triisopropylantimony, tri-n-butylantimony, tri-5ec-butylacetimo/, tri-inbutylantimony/, triphenylantimony, and the like.

The amount of these compounds added is determined by using one or more of these compounds and
0.02 to 5 parts by weight is suitable for 00 parts by weight,
Preferably it is 0.1 to 1 part by weight. The amount of additive is 0,
02] J: If the amount is less than ii parts, curing will not be sufficient (on the other hand, if it is more than 5 parts by N, coloration may be observed in the cured product obtained).

(6) Various additives commonly used in acrylic syrups can also be added to the composition of the present invention. Here, the additives include dyes and pigments used for coloring, stabilizers such as antioxidants, ultraviolet absorbers, flame retardants, plasticizers, and fillers such as calcium carbonate and aluminum hydroxide. It is also possible to use reinforcing agents such as glass fibers and carbon fibers. In addition, chain transfer agents and crosslinking agents may be used as necessary.

Specific examples of the polymerization initiator used in the present invention include 2,2'-azobisine butyronitrile, 2,2'-
Azobis(2,4-dimethylvaleronitrile), 2.2
'-azobis(2,4-dimethyl-4-methoxyvaleronitrile), organic peroxides such as benzoyl peroxide, or redox polymerization initiators, such as organic peroxides and tertiary amines. Combinations with etc. can be mentioned. The amount of these initiators added is preferably set in the range of 0.01 to 10 parts by weight per 100N parts of the syrup.

Polymerization of the acrylic syrup composition of the present invention is normally carried out at room temperature, but if necessary, polymerization and curing may be carried out by heating in an air oven or the like.

〔Effect of the invention〕

The acrylic syrup composition of the present invention having the composition described above has curability not only in an inert atmosphere but also in an oxygen-containing atmosphere, such as air, so it can be used for casting, adhesion, lamination, etc. It can exhibit excellent properties in various applications.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

In addition, parts in Examples mean parts by weight and weight %, respectively.

Example 1, Comparative Example 1 Methyl methacrylate syrup with a polymerization rate of 21.2% lOO
1 part of Ciba-Geigy Co., Ltd. Chinubi/(trademark) Po, 0.3 parts of 2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile) and 10.3 parts of triphenylphosphine were added to Dissolved uniformly.

As a comparative example, the above composition was also prepared without the addition of triphenylphorasphine. Next, these syrup compositions were poured into aluminum cups to a thickness of 10 mm. This was left in an air atmosphere at a room temperature of 26° C. and its curing properties were observed.

The product to which triphenylphosphine was added gradually generated heat and curing was completed in about 2 hours, showing optical hardness, but the product without triphenylphosphine lost its surface layer within about 2 hours. It was in a soft state that was not fully cured, and remained in a semi-cured state even after 18 hours.

Examples 2 to 9, Comparative Examples 2 to 5 Curing was performed in the same manner as in Example 1 using the compositions and curing conditions shown in Table 1, and the curability was measured. The obtained results are shown in Table 1.

(9)

Claims (1)

[Scope of Claims] 1. A) A partial polymer of methyl methacrylate alone or a monomer mixture containing methyl methacrylate as a main component, B) General formula R, 1 to 4 alkyl groups, or unsubstituted or substituted i◇enyl groups, where X represents phosphorus, arsenic, or antimony); and C) an acrylic syrup composition comprising a radical polymerization initiator. 2. The amount of the compound represented by the general formula CD used is 0.0 parts by weight per 100 parts by weight of a partial polymer of methyl methacrylate alone or a monomer mixture containing methyl methacrylate as the main component.
The acrylic syrup composition according to claim 1, characterized in that the amount is 2 to 5 parts by weight.