JPS61174263A - Flame-retardant thermoplastic synthtic resin composition for molding film - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which has excellent flame retardance, toughness and film-moldability and gives a film having excellent surface smoothness and suitable for use in the surface decoration of incombustible, sound absorbing interior finish materials, by blending a thermoplastic synthetic resin with an inorg. filler. CONSTITUTION:A 30-60wt% thermoplastic synthetic resin (A) (e.g. PP or PS) having a glass transition temp. of 50-120 deg.C and contg. no halogen, 40-70wt% inorg. filler (B) composed of 5.2-43pts.wt. colloidal inorg. fiber (e.g. potassium titanate fiber) having a fiber diameter of 3mu or below, a fiber length of 30mu or below and an aspect ratio of 10 per 100pts.wt. inorg. powder [e.g. Al(OH)3 or Mg(OH)2] having a particle size of 40mu or below, which is dehydrated by heating, and additives (C) such as thermal stabilizer, ultraviolet light stabilizer, plasticizer, lubricant, antistatic agent, thickener, dispersant, etc., are kneaded with heating in an extruder.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flame-retardant thermoplastic synthetic resin composition for film molding that has a high degree of flame retardancy, toughness, and excellent calendar moldability. The obtained film is mainly used as a nonflammable, heat-insulating, sound-absorbing film, and as a decorative surface film for interior materials.

[Conventional technology]

Conventional flame retardant technology for synthetic resins involves adding flame retardants such as halogen compounds, phosphorus compounds, nitrogen compounds, and antimony oxide to synthetic resin raw materials. Flame retardants are relatively expensive, and
There is a risk of generating harmful gases during molding or when exposed to high temperatures.

In recent years, attempts have been made to make flame retardant by filling synthetic resin with non-hazardous inorganic fillers. It is necessary to incorporate a large amount of the film into the film, which reduces the moldability of the film and deteriorates the strength of the film.

In order to improve this, attempts have been made to reduce the amount of inorganic filler by using the flame retardant and inorganic filler together, but not only is it difficult to obtain a sufficient flame retardant effect, but also thermoplastic Since the amount of inorganic filler used in combination with the synthetic resin cannot be reduced to that extent, the moldability of the film is reduced and the strength of the film is deteriorated.

In order to improve this, attempts have been made to reduce the amount of inorganic filler by using the flame retardant and inorganic filler together, but the effect may not be sufficiently demonstrated or it may not directly lead to improved moldability. do not have.

On the other hand, in order to improve the moldability of the film, a synthetic resin with a relatively low molecular weight is sometimes incorporated, but the low molecular weight synthetic resin has a low softening point, so the toughness is reduced. In addition, various lubricants and plasticizers such as aluminum stearate and metal soap are sometimes added, but these do not substantially improve flame retardancy or toffee properties.

[Problem that the invention seeks to solve]

This invention solves problems that could not be solved by making conventional synthetic resins flame retardant, such as the generation of harmful gases that occur during molding or when exposed to high temperatures, and the deterioration of moldability caused by flame retardation. strength of.

(Objective of the present invention is to obtain a synthetic resin composition having high flame retardancy, toughness, and moldability without deterioration in toughness.)

[Means for solving problems]

30 to 60% by weight of a thermoplastic synthetic resin having a glass transition temperature of 50 to 120°C and containing no rogens, and 52 parts by weight of colloidal inorganic fiber to 100 parts by weight of heat-dehydrated inorganic powder.
The problem was solved by obtaining a composition containing 40-70% by weight of an inorganic filler containing ~43 parts by weight.

[For production]

The composition of this invention has a glass transition temperature of 50 to 120'.
In C, an inorganic filler consisting of a heat-dehydrated inorganic powder and a colloidal inorganic fiber is blended with a halogen-free thermoplastic synthetic resin, so it can be used during kneading for composition formation or film formation. During molding, the water vapor generated from the heat-dehydrated inorganic powder evaporates through the gaps between the colloidal inorganic fibers, and with the added reinforcing effect of the colloidal inorganic fibers, the surface smoothness and toughness are improved, and the heat-dehydrated inorganic powder is It combines the excellent flame retardancy of an inorganic filler made of molded inorganic powder and colloidal inorganic fibers.

〔Example〕

The composition of the present invention has a glass transition temperature of 50 to 120°C, 30 to 60% by weight of a halogen-free thermoplastic synthetic resin, and 5.2 parts by weight of colloidal inorganic fibers per 100 parts by weight of heat-dehydrated inorganic powder. It is made by blending 40 to 70% by weight of an inorganic filler containing ~43 parts by weight, and the glass transition temperature used here is 50 to 120°C, and as a halogen-free thermoplastic synthetic resin. , for example polyethylene, polypropylene, polystyrene.

Polymethacrylic acid ester, polycarbonate.

Polyethylene terephthalate and copolymers thereof are advantageously used, and the heat-dehydrated inorganic powder has a particle size of 4.
0 μ or less aluminum hydroxide, magnesium hydroxide,
Hydrated calcium sulfate or a mixture thereof is used, and talc, clay, calcium carbonate, etc. may be partially substituted as long as flame retardancy and moldability are not impaired.

Furthermore, as colloidal inorganic fibers, titanic acid strained fibers,
Boron nitride fiber, calcium metasilicate (wollastonite)
, sepiolite, Hedman fiber, etc., with a fiber diameter of 3 μm or less, a fiber length of 30 μm or less, and an aspect ratio of about 10.

Therefore, the composition of the present invention has the above-mentioned heat-dehydrated inorganic powder 1.
00 parts by weight, 40 to 70 parts by weight of an inorganic filler mixed with 52 to 43 parts by weight of colloidal inorganic fibers, and 30 to 60 parts by weight of a halogen-free thermoplastic synthetic resin with a glass transition temperature of 50 to 120°C. % by a heating kneading method using a pressure roll, a kneader-2 extruder, etc., and further, in order to obtain the desired film from the obtained composition, an extruder is used. After the film is preformed, it is rolled and formed into a film using a calendar roll or the like.

In addition, the composition of the present invention may contain a known heat stabilizer to the extent that it does not impede the properties required of the composition.

Ultraviolet stabilizers, plasticizers, lubricants, antistatic agents, thickeners, dispersants, etc. may be added and blended as appropriate.

Next, in order to know the flame retardance of films obtained from the compositions of the present invention with various formulations, flammability, tensile strength, elongation, t
2. Table 1 shows the results of measuring moldability and smoothness.

The thermoplastic synthetic resin has a density of 0.865. Ethylene content 1
A 2% fA binding polypropylene ethylene copolymer was used, but in Composition 4, high density polyethylene with a density of 0945 was used.

As the heat-dehydrated inorganic powder which is one component of the inorganic filler, aluminum hydroxide (trade name: Hisilite, manufactured by Showa Denko K.K.) with an average particle size of 30 μm was used. However, Example 2
-4. ．． In 5-5, calcium carbonate with an average particle size of 30 μm was used. The colloidal inorganic fiber, which is the other component of the inorganic filler, has a fiber diameter of 3μ or less, a fiber length of 30μ or less, and a colloidal potassium titanate fiber [trade name Teismo, manufactured by Otsuka Chemical Co., Ltd.] with an aspect ratio of 10. Example 5-5
In this case, glass fiber powder having an average fiber diameter of 5 p and an average fiber length of 100 μm was used. Each composition was manufactured by heating and kneading in a pressurized niegu to obtain a composition.

For the measurement of combustibility for testing flame retardancy and for measuring tensile strength, the composition was placed on a flat press machine, heated and pressurized at 160 ° C. for 5 minutes using a spacer, A film with a thickness of 0.1 m was made and cut into appropriate sizes, and five sheets were prepared for each sample.

Flammability was measured using the horizontal ignition flame method, which complies with the Ministry of Transport's 1 Vehicle Materials: ':i Combustion Test Standard FMVSS-302J. The time was measured 5 times per sample,
The times for the five times were added up and the total number of seconds was displayed.

The tensile strength is 0.1 m thick molded in the same manner as above.
The film was cut into 15 mm widths and subjected to a tensile test, and the results were expressed as breaking strength and elongation at break at 15 mm width.

Confirmation of moldability is determined by the moldability when making a 0.1 mm thick film using a calendar roll molding machine equipped with an extruder preforming device and the smoothness of the film after molding, and is indicated by the following symbol categories. did.

Moldability ◎Things that can be easily molded △Things that are suitable for molding △Things that can be made into sheets continuously regardless of appearance Items with no problems △ Items with pinholes, fish eyes, and poor topography × Items with holes, bumps, etc. that are unusable When mixing only dehydrated inorganic powder, the higher the mixing ratio, the lower the flammability and the higher the flame retardancy, but the lower the breaking strength and the lower the elongation at break, and the lower the film formability.

It is understood that both film smoothness deteriorates rapidly. In contrast, as in the present invention, thermoplastic synthetic resin 30 to 6
Compared to 0% by weight, a mixture of 40 to 70% by weight of an inorganic filler consisting of heat-dehydrated inorganic powder and colloidal inorganic fibers becomes flame retardant as the flammability decreases as the amount of inorganic filler increases. Although the strength at break increases slightly and the elongation at break decreases, there are no problems with both film formability and film smoothness. , a decrease in flammability, that is, an improvement in flame retardancy and an improvement in breaking strength can be observed.

If the amount of inorganic filler is less than 40% by weight, problems will arise in flame retardancy, and if it exceeds 70% by weight, the breaking strength of the film will decrease, resulting in poor film formability.

Smoothness also deteriorates. Furthermore, when the amount of colloidal inorganic fiber is less than 52 parts by weight based on 100 parts by weight of heat-dehydrated inorganic powder, no effect is observed due to the addition of colloidal inorganic fiber, and when it exceeds 43 parts by weight, the moldability of the film deteriorates. , the smoothness deteriorates.

〔Effect of the invention〕

As described in detail above, the glass transition temperature is 50 to 120.
Halogen-free thermoplastic synthetic resin 30-6 °C
0% by weight and 100 parts by weight of heat-dehydrated inorganic powder,
The composition of the present invention contains 40 to 70% by weight of an inorganic filler containing 5.2 to 43 parts by weight of colloidal inorganic fibers,
The film has excellent film formability, especially by calendar molding, and the resulting film has excellent surface smoothness, is flame retardant, does not emit harmful gases, and is suitable for use with inorganic fillers, especially heat-dehydrated inorganic fillers. The combination of powder and colloidal inorganic fiber forms a film that does not reduce its strength or toughness, and exhibits remarkable effects as a surface decorative film for interior materials that are nonflammable, heat insulating, and sound absorbing. be.

Patent applicant: Nittobo Co., Ltd. Agent: Patent Attorney Katsu Ohno Reiko Irino Yanosuke Ohno

Claims (1)

[Claims] 5.5% by weight of colloidal inorganic fiber based on 30% to 60% by weight of a thermoplastic synthetic resin having a glass transition temperature of 50 to 120°C and containing no halogen, and 100 parts by weight of heat-dehydrated inorganic powder.
A flame-retardant thermoplastic synthetic resin composition for film molding, which is blended with 40-70% by weight of an inorganic filler containing 2-43 parts by weight.