JPS6084378A - Ultraviolet light absorber - Google Patents

Abstract

PURPOSE:To provide an ultraviolet light absorber which has limited solubility in the contents of synthetic resin containers and prevents the contents from being deteriorated by light, by reacting an ethylenically unsaturated carboxylic acid-modified PE with a specified compd. CONSTITUTION:A modified PE having an ethylenically unsaturated carboxylic acid content of 0.1-30wt% and a weight-average MW of 1,000-10,000 obtd. by reacting an ethylenically unsaturated carboxylic acid or its anhydride with a (co)polymer mainly composed of an alpha-olefin, is reacted with a compd. of the formula (wherein R, R' are each H, a 1-24C aliph. hydrocarbon group; Y is H or an OH group-contg. hydrocarbon group; l, m are each 0-3).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an ultraviolet absorber, and more particularly to an ultraviolet absorber that can be suitably used to prevent photodeterioration of the contents of various synthetic resin molded containers.

Prior Art In order to protect the contents of various synthetic resin molded containers, especially transparent plastic containers, from UV deterioration, attempts have been made to mix UV absorbers into plastic containers. Due to the problem of elution into substances, there was a limit to its practical application. For this reason, plastic containers are colored or wrapped in paper to shield the contents from light. However, this is undesirable because it detracts from the advantage of a transparent container in that the contents are visible from the outside. This is due to the high solubility of the ultraviolet absorber used in the solvent.

OBJECTS AND STRUCTURE OF THE INVENTION Accordingly, an object of the present invention is to add y8 M! to a solvent. For example, when blended into a PlusDeck container to protect the contents from ultraviolet deterioration, ultraviolet rays can suppress elution into the contents and virtually prevent contamination of the contents. The purpose is to provide an absorbent.

According to the present invention, (A) the content of ethylenically unsaturated carboxylic acid units is 0.1 to 30% by weight and the weight average molecular weight is 10
(I3) general formula -) (wherein R and Ro are each independently a hydrogen atom or carbon)
1 to 24 aliphatic hydrocarbon groups, Y represents a hydrogen atom or a hydrocarbon group containing hydroxyl, β and I'1
1 is independently 0 to 3).
UV absorbers are provided.

As described above, the ultraviolet inhibitor according to the present invention has a content of (A) ethylenically unsaturated carboxylic acid units of 0.1 to 30% by weight and a weight average molecular weight of 1000 to 30% by weight. 10,000 is reacted with (B) the compound of the general formula -) (η).

The modified polyethylene (A) is ethylene, propylene,
butene-11 pentene-1,3-methyl-butene-1,
Polyolefin as a polymer or copolymer mainly composed of α-olefin such as hexene-1,4-methylpentene-1 is modified with ethylenically unsaturated carboxylic acid or its anhydride. , the latter is modified by copolymerization or kraft polymerization.

As the ethylenically unsaturated carboxylic acid or its anhydride, it is often preferable to use acrylic acid, maleic acid, itaconic acid, hemi-heptalic acid, or anhydrides thereof, particularly maleic anhydride and acrylic acid. .

Amorphous 1,2-polybutadiene in which maleic anhydride is added to the tertiary carbon position may also be used.

Copolymerization method with olefin and ethylenically unsaturated carbonic acid,
The graft polymerization method may be a conventionally known method.

(For example, see Japanese Patent Publication No. 3B-23494 v1, Japanese Patent Publication No. 43-18393, and Japanese Patent Publication No. 44-9908.) Graph 1 - Polymerization is performed by irradiation with ionizing radiation, ultraviolet rays, etc. Graft polymerization is carried out by graft initiation methods such as a method using a radical initiator, a method of peroxidation by the action of oxygen, osone, or heat, and a method using heat and shear force in a kneader. The graft polymerization can be carried out in a solution state, slurry state, melt state, etc.

As mentioned above, the modified polyolefin thus prepared has an ethylenically unsaturated carboxylic acid unit content of 0.1.
~30% by weight with a weight average molecular weight of 1000-10000
Must. When the content of ethylenically unsaturated carboxylic acid units is O, 1% by weight, the amount of ultraviolet absorber in the reaction product when reacted with the compound (general formula day) is small, conversely 30% by weight If it exceeds %, the compatibility with the resin will decrease when the product produced by reacting with the compound of general formula (1) is blended into the resin, which will adversely affect the appearance and physical properties of the resin composition, which is not preferable. In addition, when the weight average molecular weight is less than 1000, when the reaction product with the compound (general formula day) is blended into the resin, embossment on the surface is observed due to the low molecular weight, and the surface of the molded product becomes tacky. It was not possible to put it into practical use because of the adhesion of dirt and dust.
If it exceeds 0, the reactivity with the compound of general formula (1) decreases, which is not preferable. This is considered to be because the molecular weight of the modified polyolefin becomes too large and the molecular mobility decreases.

A modified polyolefin suitable for use has an ethylenically unsaturated carboxylic acid unit concentration of 0.5 to 20% and a molecular weight of 2.
000 to 8,000, more preferably the ethylenically unsaturated carboxylic acid unit concentration is 1.0 to IO P% and the molecular weight is 2,000 to 5,000.

The substituents R and Ro (R and Ro
(which may be the same or different) are preferably hydrogen atoms or aliphatic hydrocarbon groups having 1 to 5 carbon atoms (specifically methyl, ethyl, butyl groups, particularly preferably methyl group), and ρ and nl are preferably 0-2. By changing the number of m, the ultraviolet absorption region of the ultraviolet absorbent of the present invention can be changed. Further, as mentioned above, the substituent Y of the compound of general formula (1) is a hydrocarbon group having a hydrogen atom or an ice @ group, preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms substituted with a hydroxyl group. It is a hydrogen group. Substitution from the point of view of reactivity with ethylenically unsaturated carbonic acid of modified polyethylene! i! It is preferable that it is a hydrocarbon group substituted with i Y cJ hydroxyl and having 1 to 4 carbon atoms, and it is particularly preferable that -OY is in the para position.

The compound of the general formula (1) can be produced, for example, as follows.

(11) (III) C) (IV) Therefore, 60 g of compound (II) and 26 g of compound (In)
was placed in a flask purged with nitrogen, 100 mg of dried potassium carbonate was added, the temperature was raised to 180 °C, and stirring was continued. After stirring for 4 hours, the mixture was returned to room temperature after no carbon dioxide gas was generated and the mixture was observed to have a solid appearance. The resulting reaction mixture was dissolved in acetone/8, reprecipitated in water, washed with water, and then recrystallized from acetone +1.
The target compound (1) was synthesized.

Similarly, the following compounds were synthesized.

Next, the reaction between the modified polyolefin and the compound of general formula (1) can be carried out using, for example, the conventionally known reaction force method between an acid anhydride and a hydroxyl group. Although the method is not limited, more specifically, the modified polyolefin may be brought into a molten state, and the compound of general formula (1) may be added thereto for reaction.

By applying this uniform melt pressure 15 using an extruder, it is possible to react the modified polymerefin with the compound of general formula (1) while kneading it with the resin.
Thereby, an ultraviolet deterioration-resistant resin composition containing the reaction product can be obtained.

In addition, another method is shown in which the modified polyolefin is dissolved in a boiling xylene solvent.
can be reacted by adding a compound. Further, at this time, for example, if pyridine is used as a base catalyst, the reaction can be further promoted. After the reaction is completed, the reaction product can be obtained by lowering the temperature and reprecipitating in a solvent such as methanol, followed by filtering and drying. A UV deterioration-resistant resin composition can be obtained by using a predetermined amount of this and kneading it with a desired resin using an extruder or the like. resin 111
In order to obtain the composition by a simple method, the modified polyolefin, the compound of general formula (1), and the resin may be mixed simultaneously to prepare a ζ resin composition. As described above, the resin composition containing the ultraviolet absorber according to the present invention includes polyethylene (IID, LD, LLD, M-MA copolymer,
copolymer), polypropylene (IPP, random, α-olefin copolymer), borisdyrene, polymethylmethacrylate-1, poly4-methylpentene-1, polycarbonate-1, polyester, nylon , ABS, etc., but also mixtures of the above resins, polymer alloys, etc.

Although it cannot be further defined by the mixing ratio of these resins and the reaction product & 1.1 concentration of the compound of general formula (1) in the reaction product, it is possible that the compound of general formula (1) is present in the resin composition at 0%. The content may be set to .05 to 5% by weight. However, if the amount of the reaction product in the cedar fat composition exceeds 30% by weight, the inherent properties of the resin will deteriorate, so the amount of the reaction product should be at most 30% by weight. The Kraft ultraviolet absorber shown here has extremely low solubility in β11-tension ethanol and room temperature hexanoyl, and is therefore hygienically safe, with no problem of elution and transfer to sake, urakaryo, etc.

Although the present invention will be described in detail below, it goes without saying that the scope of the present invention is not limited to these Examples.

500 g of polyethylene with a molecular weight of 2500 and grafted with 3.5% by weight of maleic anhydride was placed in a reaction tank of 101.
After melting at 40°C, compound 54 of the formula (V)
10 ml of pyridine was added thereto while stirring, and the mixture was allowed to react for 2 hours. Then add xylene flOml and 1f
After lowering the temperature to room temperature while stirring f2, methanol (8j2) was added and reprecipitated. After the reaction η binary product was filtered off, it was poured with acetone 81, filtered off again, unreacted compound (V) was washed away, and the mixture was dried under reduced pressure at room temperature.

The IR analysis result of the product is 1790 cm (ν( of acid anhydride)
C=O)) completely disappeared and a new 1740cm'(
Absorption appeared at ν (C=0) of the ester and at 1700 cm-' (ν (C=O) of the acid), and the above compound (■) reacted with the acid anhydride portion.

Example 2 In Example 1, the compound of formula (IV) was replaced with the compound of formula (V).
) The reaction product of modified polyethylene and compound (1v) was prepared in the same manner as in Example I except that 60 g of compound (1v) was used.
I was massaged. The [R analysis results of the product were also the same as in Example 1.

10 g each of the reaction products of Examples 1 and 2 and B ITo,
3g and polyethylene (Shorex F134) 150
I blended each g! 20 dragon φ at 10℃
It was pelletized using an extruder.

Each pellet obtained in this way was heated to 170°C with Q,
It was compression molded into a press sheet with a thickness of l m++.

The 330 nm UV transmittance (%) of this press sheet was measured. The results are shown in the table below. Also, the above press sea 1
- is extracted with boiling acetone for 2 hours, the same <330
The transmittance (%) of nmUV was measured.

The results are also shown in the table below.

Comparative Example 1 150 g of polyethylene (Shorex F134), 0.75 g of the compound of formula (V) and B II l''
When I mixed 0.3g with a mixer, it was 20! III
Pelletization was performed using a φ extruder, a press sheet was prepared in the same manner as in Examples 1 and 2, and the UV transmittance (%) of the press sheet and the press sheet after acetone extraction was measured.

The results are shown in the table below.

Comparative Example 2 150 g of polyethylene (Shorex F134) and the same modified polyethylene (MW250) used in Example 1
0) lOg and 0.3 g of B II T were mixed and pelletized in the same manner as in Example 1 using a 20-diameter extruder. Press Sea 1 using a method similar to Example 1
- was prepared and the UV transmittance (%) was measured. The results are shown in the table below.

LIV (330nm) 'lxl weight ratio) NO with acetone extraction 1, press sheet Press saw 1 Example 1 <1 <1 Example 2 <1 '<1 Comparative example 1 <1 92 Comparative example 2 91 91

Claims (1)

[Claims] (8) The content of ethylenically unsaturated carboxylic acid units is 0.1 to 30% by weight and the weight average molecular weight is 1000 to 10.
(B) = General formula (1) (wherein R and R each independently represent a hydrogen atom or an aliphatic hydrocarbon group having 1 to 24 carbon atoms, and Y represents a hydrogen atom or a hydroxyl group. (where p and in are each independently 0 to 3) are reacted to produce 1η.