JPS60188428A - Modification of poly(p-phenylene sulfide) - Google Patents

Abstract

PURPOSE:To alleviate a decrease in modulus of elasticity at high temperatures and a decrease in toughness due to crystallization, by adding a specified compound to poly(p-phenylene sulfide) and then removing this compound from the mixture. CONSTITUTION:At least one compound selected from the group consisting of AlCl3, FeCl3, and TaF5 is added to poly(p-phenylene sulfide) (hereinafter, abbreviated as PPS) and then removed from the mixture. When the above compound is gaseous or has a high vapor pressure at room temperature, PPS in the form of, for example, sheet is added to an atmosphere of its vapor. When the above compound has a low vapor pressure at room temperature, it can be added to PPS by forming an atmosphere of the compound by heating in vacuum. The additive is removed because unless it is removed, the insulating property is injured. It is possible to improve the modulus of elasticity of the polymer at near room temperature without detriment to its insulating property and to allow it to retain its high modulus of elasticity up to a higher temperature.

Description

Detailed Description of the Invention (Technical Field) The present invention improves the elastic modulus around room temperature while maintaining insulation properties by chemically treating a film made of polyparaphenylene sulfide. The present invention also relates to a method of maintaining a high elastic modulus even at higher temperatures.

(Prior art) Polyparaphenylene sulfide (hereinafter abbreviated as PPS) has superior chemical resistance, heat resistance, insulation, high frequency properties, and nonflammability compared to other thermoplastic resins, and has It is expected to be used not only for molding purposes but also as a film, making use of these properties in electrical equipment parts, automobile parts, aircraft parts, etc.

General PPS has a glass transition point around 90° C., and has the disadvantage that it begins to soften at temperatures above this temperature and becomes extremely brittle as the degree of crystallinity progresses. This poses a problem in that its use in fields that require flexibility at high temperatures is severely limited.

(Objective of the present invention) The inventors of the present invention conducted extensive studies with the aim of improving the disadvantages of PPS film, such as a decrease in elastic modulus at high temperatures and a decrease in toughness due to crystallization. We have discovered that by adding and then removing the compound, it is possible to maintain a high elastic modulus up to higher temperatures while maintaining insulation properties, and to prevent the weakening of the film due to crystallization, and have arrived at the present invention.

In other words, the present invention is characterized in that the crystallization and melting point peaks measured by differential scanning calorimetry 81 disappear or become unclear, the glass transition temperature is 100°C or higher, and the elastic modulus measured by dynamic viscoelasticity measurement is 100°C or higher. But 10” dyn/
The present invention provides a method for obtaining PPS that maintains a value equal to or higher than af by adding a specific compound and then removing the compound.

(Structure of the present invention) The purpose of item -F of the present invention is to add one or more compounds selected from AI CI 3, Fe Cl 3 and Ta Fs to polyparaphenylene sulfide, and then remove the compound. This is achieved by

It is a polymer containing 90 mol% or more, preferably 95 mol% or more of repeating units represented by In addition, the PP used
S can contain ordinary additives such as particulate fillers such as fused silica, mica, and glass peas, lubricants, and colorants, and can also be blended with a small proportion of a polygonal polymer as long as it does not impede the present invention. .

In the present invention, the PPS sheet-like material refers to non-oriented, -axially oriented,
Any biaxially oriented polymer is a plate-like polymer with a thickness of 1 mm or less, preferably a film-like polymer with a thickness of 100 μm or less. This PPS sheet-like product can be formed by extrusion molding, compression molding, etc., but it is preferable to manufacture it by extrusion molding.

In order to obtain PPS sheets having the novel properties of the present invention, it is necessary to add an electron-accepting compound to the PPS polymer. In the present invention, as an electron-accepting compound, Δl
C13, Fe C13, and l'a r5, and one or more compounds selected from these are used. Compounds that are gaseous or have a high vapor pressure at room temperature can be added to PPS by exposing the PPS to a gas atmosphere. A compound having a low vapor pressure at room temperature can be added to PPS by heating it in a vacuum to create an atmosphere of the compound.

On the other hand, it is also possible to dissolve the above compound in a suitable solvent and add the compound to PPS in this solution. The solvent used here may be any solvent that dissolves the above compound, such as methylene chloride, dichloroethane, benzene, toluene, N-methylpyrrolidone, etc., but nitromethane is particularly preferably used. The compound can be added by immersing a sheet of PPS in this solution, but it is also possible to heat the solvent at this time in order to speed up the addition rate. Also, by mixing the compound into PPS powder,
A film containing the additives can also be obtained by molding this into a film using a hot press or the like.

The above-mentioned addition treatment time requires time until the compound is sufficiently added to PPS, and varies depending on the added compound. For example, when immersing in an AI Cl 3 solution, about 30 minutes is sufficient. The addition ma of the compound is P
The amount is preferably 5 to 40 mol % per monomer unit of PS; if more is added, crosslinking occurs between adjacent phenyl groups in the PPS molecule depending on the additive compound, thereby making the PPS film brittle.

The sheet-like PPS used in the present invention may be unstretched, 5-uniaxially stretched, biaxially stretched, or heat-treated to improve crystallinity. However, sheet-like PPS that has not been stretched or heat-treated generally has a fast addition rate and can be easily processed according to the present invention.

P, P to which an electron-accepting compound was added as described above
S becomes dark green or black, and in this state the novel properties of the present invention can be obtained, but the insulating properties are impaired if left as is, so the additives are removed and the film is returned to its original transparent state.

(Effects of the Present Invention) According to the present invention, it is possible to improve the elastic modulus near room temperature while maintaining insulation properties, and to maintain a high elastic modulus up to higher temperatures.

The present invention will be described in detail below based on Examples.

Example 1 AICl s was added to PPS by dissolving AICI 32 (l) in 20 cc of nitromethane and immersing the PPS film in this solution in a nitrogen atmosphere. The PPS film used here was an unstretched 6-film. The thickness of PPS is approximately 50μ. PPS turns green immediately after immersion, and after 10 minutes it turns black.
From room temperature to 28°C at a heating rate of 2°C/min and an IZ of 110°C.
Measurements were made in the range up to 0°C.

The elastic modulus of the PPS film that had not been subjected to additive treatment suddenly decreased from around 80°C, and measurement became impossible at temperatures above 100°C. On the other hand, PPS with AI Cl 3 added is 1
It maintained an elastic modulus of 10" dyn lc1 or higher at 53°C.

Example 2 Addition of FeCl3 to PPS by dissolving 0.3 (I of FeCl3 in a solvent consisting of nitromethane and methylene chloride and dipping an axially stretched PPS film (20μ thick) into this solution in a nitrogen atmosphere) After being immersed for about 45 minutes, it was taken out and washed with water.The temperature dispersion of elastic modulus was measured in the same manner as in Example 1.

The elastic modulus of the untreated PPS film starts to decrease around 80°C and becomes less than 10Iodyn/at at 124°C, whereas the one treated with FeC13 maintains an elastic modulus of more than 10IOdyn/at up to 143°C. At Cl s was added to the PPS by soaking the axially stretched film (20μ thick) for 30 minutes. After washing with water and vacuum drying, the temperature dispersion of the elastic modulus was measured in the same manner as in Example 1.

Unstretched PPS film has an elastic modulus of 2.9X near room temperature.
10' dyn/CxI, which starts to gradually decrease from near 80°C, whereas the PPS film treated with AI CI 3 has a temperature of 4.7
It shows an elastic modulus of yn/c/, and no large change in the elastic modulus is observed up to around 120°C.

PerkinElmer differential scanning calorimeter "DSC-2"
When the film treated with AI C1g was measured using ``, no peak associated with crystallization appeared, which suggests that intermolecular crosslinking is promoted by the method according to the present invention.

Example 4 TaF5 was placed in the bottom of a vacuum container, a biaxially stretched P, PS film (20μ thick) was placed on top of the container, and the bottom was heated to 100°C to form a PPS film in a TaF5 gas atmosphere. TaF5 was added.

The temperature dispersion of the elastic modulus of this film was measured in the same manner as in Example 1. The film before processing is around room temperature r2.9X1
0Iodyn/- and gradually decreases from around 80°C, whereas PPS with T''Fs added
The film is 3.7×10Iodyn/aK near room temperature.
It has an elastic modulus of 10Iodyn 1 up to around 150℃
Maintains an elastic modulus of 0+f or more.

When measurements were performed using a differential scanning calorimeter in the same manner as in Example 3, no peaks associated with crystallization were observed. This indicates that intermolecular 9-crosslinking is progressing due to the addition of TaF5.

10-

Claims (1)

[Claims] (1) AI C1s on polyparaphenylene sulfide
A method for modifying polyparaphenylene sulfide, which comprises adding one or more compounds selected from , FeCIg, and TaF5, and then removing the compound.