JPH02135238A - Surfactant-containing weatherable resin composition having improved susceptibility to discoloration - Google Patents

Abstract

PURPOSE:To obtain the subject composition useful as packaging film, agricultural house, non-fogging covering material for tunnel, etc., or antistatic film having excellent weatherability and color fastness containing weatherability- imparting agent of hindered amine-system and neutralized surfactant. CONSTITUTION:The aimed composition contains a weatherability-imparting agent of hindered amine-system (preferably 2,2,6,6-tetraalkylpiperidine derivative having substituting group at 4-position and >=250 molecular weight, e.g., compound expressed by the formula) and a surfactant in which residual alkali catalyst component is neutralized (preferably nonionic surfactant).

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a weather-resistant resin composition containing a surfactant. Specifically, the present invention relates to a surfactant-containing weather-resistant resin composition that has improved quality problems related to discoloration.

<Prior Art> The amount of resin used outdoors is increasing year by year. These resins are required to have weather resistance depending on the purpose of use, and many weather resistance imparting agents have been developed so far.

In the past, ultraviolet absorbers such as benzophenone were used to impart weather resistance to resins, but recently HA
A hindered amine weathering agent called LS is often used because of its high performance. For example, Japanese Patent Publication No. 59-86645 discloses a weather-resistant resin composition containing this weather-resistant agent.

On the other hand, resins for outdoor use are often used specifically for agricultural films, artificial turf, and automobile exteriors, and each has different functions depending on its use, such as antifogging, antistatic, and inorganic filler properties. Various surfactants are added to resins for the purpose of imparting dispersibility and the like. As described above, the number of weather-resistant resin compositions containing surfactants is increasing year by year.

<Problems to be Solved by the Invention> However, surfactant-containing weather-resistant resin compositions containing hindered amine-based weather resistance imparting agents (often containing thermal stability rules such as hindered phenol-based stabilizers) have poor weather resistance. Although these products are excellent, they have the problem that they change color (in many cases yellow) over time when stored in warehouses as pellets, films, molded products, etc., reducing their commercial value.

In addition, this discoloration and opening is particularly noticeable in the case of hindered amine weatherability imparting agents having a triazine ring structure in the molecule, which is attracting attention as an excellent hindered amine weatherability imparting agent with a large weatherability imparting effect.

The object of the present invention is to provide a weather-resistant resin containing a hindered amine-based weather resistance imparting agent, which does not reduce weather resistance and the functions provided by surfactants to the extent that it becomes a practical problem, and which significantly suppresses the occurrence of the above-mentioned discoloration. An object of the present invention is to provide a composition.

<Means for Solving the Problems> The present inventors have continued to study surfactant-containing weatherable resin compositions, particularly surfactant-containing weatherable resin compositions containing a hindered amine weatherability imparting agent. As a result, many commercially available surfactants (particularly nonionic surfactants) use alkaline catalysts such as sodium hydroxide or potassium hydroxide during manufacturing, and the alkali catalysts are present in the final surfactant product. It often remains as it is or in the form of a salt with a weak acid such as a carboxylic acid, and this residual alkali content is neutralized with an equimolar amount of acid as a surfactant (
We have discovered that when a neutralized surfactant (hereinafter referred to as a neutralized surfactant) is used, the discoloration of a surfactant-containing weathering resin composition containing a hindered amine weatherability imparting agent is significantly improved.
The present invention has now been completed.

That is, the present invention is a surfactant-containing weather resistant resin composition containing a hindered amine weather resistance imparting agent, which is characterized by using a surfactant that has neutralized the residual alkali catalyst contained in the surfactant.

Resins used in the present invention include olefin homopolymers such as polyethylene, polypropylene, poly-1-butene, and poly-4-meth-fk-1-pentene, ethylene-propylene block copolymers, and ethylene-propylene random copolymers. , ethylene-1-butene copolymer, ethylene-
Olefin copolymers such as 1-hexene copolymer, ethylene-4-methyl-1-pentene copolymer, ethylene-1-octene lt polymer, propylene-1-butene copolymer, ethylene-vinyl acetate copolymer Copolymers of olefins and polar vinyl compounds such as ethylene-methyl methacrylate copolymers, acrylic resins such as polymethyl methacrylate, ionomer resins, polyester resins, boria-based resins, polycarbonate resins, phenolic resins, polychloride Examples include vinyl resin and polyurethane resin.

The hindered amine weatherability imparting agent used in the present invention has a molecular weight of 250 or more and has a substituent at the 4-position.
2,6.6-titraalkylpiperidine derivative,
Examples of the substituent at the 4-position include carboxylic acid residues, alkoxy groups, alkylamino groups, and substituents thereof. Further, an alkyl group or the like may be substituted at the N-position. Specifically, compounds having the following structures can be exemplified.

The compound used to neutralize the residual alkali catalyst contained in the surfactant used in the present invention is not particularly limited, but strong acids such as phosphoric acid, sulfuric acid, nitric acid, hydrochloric acid, and organic sulfonic acids are preferably used. It will be done. Moreover, it is most desirable that the amount added is substantially equimolar to the residual alkali catalyst. The method for neutralizing the residual alkali catalyst used in the present invention is not particularly limited, but the surfactant is heated above its melting point in nitrogen or an inert gas, and a small amount of strong acid is added to the molten state while stirring vigorously. A method of dropping the mixture drop by drop is preferred.

The surfactant used in the present invention varies depending on the function to be imparted to the resin and is not particularly limited, but nonionic surfactants are more preferred. Specifically, polyethylene glycol derivatives include higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts,
Higher alkylamine ethylene oxide adducts, fatty acid amide ethylene oxide adducts, polyhydric alcohol fatty acid ester ethylene oxide adducts, etc., as well as polyhydric alcohol derivatives such as glycerin monofatty acid ester, polyglycerin fatty acid ester, pentaerythritol fatty acid ester, sorbitan and sorbitol interfat. Examples include esters, sucrose fatty acid esters, fatty acid amides of ethanolamine, and polyethyleneimine derivatives.

The blending ratio of the surfactant-containing weather-resistant resin composition of the present invention varies depending on the function to be imparted to the resin, and is not particularly limited, but is usually used in the following blending ratio.

The hindered amine type weather resistance imparting agent is generally used in an amount of 0.01 to 10 parts by weight, preferably 0.05 to 1 part by weight, per 100 parts by weight of the resin. If the amount is less than 0.01 part by weight, the effect of imparting weather resistance is poor, and if it exceeds 10 parts by weight, no further significant improvement in the effect of imparting weather resistance is observed, which is also uneconomical.

The blending ratio of the surfactant is based on 100 parts by weight of the resin.
It is usually used in a range of 0.01 to 8.0 parts by weight, preferably 0.1 to 10 parts by weight.

If the amount is less than 0.01 part by weight, the performance of the surfactant will not be fully expressed, and even if it is used in excess of 80 parts by weight, not only will no further significant improvement in the performance of the surfactant be observed, but the surface The activator causes bleeding on the surface of the resin composition, resulting in adverse effects such as deterioration of appearance.

The surfactant-containing weather-resistant resin composition of the present invention may contain various stabilizers such as a heat stabilizer, a light stabilizer, an ultraviolet absorber, an antioxidant, an anti-fogging agent, an antistatic agent, etc., within a range that does not impair the purpose of the present invention. Inhibitors, lubricants, fillers, flame retardants, pigments, etc. can be included as ingredients.

The method of blending the above-mentioned components is not particularly limited, and they can be blended by a common method such as a Banbury mixer, mixing roll, or extruder.

<Effects of the Invention> According to the present invention, by using the neutralized surfactant of the present invention in a surfactant-containing weather-resistant resin composition containing a hindered amine-based weather resistance imparting agent, weather resistance and surfactant-imparting properties can be improved. It is possible to obtain a surfactant-containing weather-resistant resin composition that does not reduce the performance imparted to such an extent that it becomes a practical problem and that significantly suppresses the occurrence of discoloration.

As shown in the Comparative Examples described later, a surfactant-containing weather-resistant resin composition without a neutralizing surfactant is subject to significant discoloration, depending on the nature of the surfactant contained.

On the other hand, when a neutralized surfactant is used, the occurrence of discoloration is significantly suppressed. Moreover, by using a neutralized surfactant, the weather resistance and the performance imparted by the surfactant are not reduced to such an extent that it becomes a practical problem.

The surfactant-containing weather-resistant resin composition of the present invention is a film,
It can be molded into sheets, fibers, various shapes, etc. and used for a variety of purposes. In particular, polyethylene as resin,
Obtained from the surfactant-containing weather-resistant resin composition of the present invention when using a polyolefin such as an ethylene-1-butene copolymer or an olefin-polar vinyl compound copolymer such as an ethylene-vinyl acetate copolymer. The film is extremely useful as a packaging film, an anti-fog covering material for agricultural greenhouses and tunnels, and an anti-static film.

<Examples> Examples of the present invention will be shown below, but the present invention is not limited thereto. In addition, the test method in the examples is as follows.

Yellow index (Yo and Y2): represents the degree of yellowness of the test piece; the lower the value, the lower the degree of yellowness.

Measurement was carried out using an SM color computer (■) manufactured by Suga Test Instruments (■). Y I to and Y I to are the values before and after the discoloration acceleration test (described later), respectively. Y engineering. -Y Engineering. = ΔYl, and a small value of ΔY indicates that the progress of discoloration is slow.

Discoloration acceleration test: A test piece with a thickness of 1 mm was left in an oven maintained at 60° C. and 90% relative humidity for 20 days.

Weather resistance test: A test piece with a thickness of 75 μm punched out with a No. 8 dumbbell was tested using a Sunshine Super Long Life Weather Meter (manufactured by Suga Test Instruments) under the conditions of a black panel temperature of 88°C and showering for 18 minutes every 12 hours. It was aged in

Tensile tests were performed on the aged test pieces using Autograph ■DSS 100 manufactured by Shimadzu Manufacturing Co., Ltd., and the elongation rate (
%) was measured, and the weather resistance test time (hereinafter referred to as weather resistance half-life) when the elongation rate became half of the elongation rate of the original test piece was determined. The larger the time value, the better the weather resistance.

Anti-fogging test: After aging a 75 μm thick test piece at 80°C for 10 days, one side of the test piece was brought into contact with 60°C saturated steam, and the other side was placed in a humid atmosphere at room temperature. The degree of cloudiness was visually measured every 15 days.

Evaluation criteria ◎ No water droplets attached O Water droplets attached less than 10% of the total area of the film △
〃 80% or less 8 “
Determination of residual alkali content in the surfactant of 50% or more: The weight fraction of alkali metals and alkaline earth metals in the surfactant was determined by atomic absorption method, and was determined as the residual alkali content.

Method for neutralizing residual alkaline content in surfactants: Surfactants with residual alkaline content (hereinafter referred to as "unneutralized surfactants")
) is melted at 100″C or less in a nitrogen atmosphere,
A neutralized surfactant was obtained by adding 86% phosphoric acid to the mixture in an amount equimolar to the residual alkaline content determined by atomic absorption spectroscopy, stirring thoroughly, and cooling.

Example 1 Melt index 2.054/10 minutes, density 0, 98
0 P/cm, ethylene-vinyl acetate copolymer with a copolymerization ratio of vinyl acetate of 5% by weight (Evatate D2048 manufactured by Sumitomo Chemical Co., Ltd.) 100 Heavyhikobe, KimaSorb ■944 manufactured by Tepa Geigy (hindered amine weather resistant) 0.85 parts by weight of the properties imparting agent (I)), 2M of tetraglycerol tristearate as the neutralizing surfactant, and Sumilizer manufactured by Seiseikagaku Kogyo Co., Ltd. as the antioxidant.
0.8 parts by weight of BPIOI was mixed with a Banbury mixer at 150° C. for 5 minutes, and then granulated with an extruder to obtain pellets.

This pellet was press-molded at 160°C to obtain a sheet with a thickness of IH. The ΔYI of this sheet was 16. In addition, this pellet was processed into a thickness of 7 mm using an inflatable machine.
It was molded into a 5 μm film, and the resulting film was subjected to a weather resistance test and an antifogging test.

Examples 2 to 4 Same as Example 1 except that the compounds shown in Table 1 were used as the neutralizing surfactant and resin, and the thickness was l +
A sheet of u and a film of 75 μm thick were obtained, respectively.

The ΔY finish of this sheet, as well as the weather resistance and antifogging properties of this film, were measured and are shown in Table 1.

Comparative Examples 1 to 6 Same as Example 1 except that the compounds shown in Table 1 were used as the unneutralized surfactant and resin, and the thickness was 1.
A sheet of n and a film of 75 μm thick were obtained, respectively.

The ΔY texture of this sheet, as well as the weather resistance and antifogging properties of this film were measured and the results are shown in Table 1. In all cases, the discoloration progressed quickly.

Comparative Example 6 A sheet with a thickness of 1 fl and a film with a thickness of 75 μm were obtained in the same manner as in Example 1 except that no surfactant was used.
The ΔYI of this sheet and the weather resistance and antifogging properties of the film were measured. As shown in Table 1, the antifogging properties were clearly inferior.

Claims (1)

[Claims] 1. A surfactant-containing weather-resistant resin composition comprising a hindered amine-based weather resistance imparting agent and a surfactant in which residual alkali catalyst content is neutralized.