DE3925521A1 - Thermally stable polyphenylene oxide - prepd. by reaction of hydroxyl-terminated mono-halo cpd. in solvent in presence of base - Google Patents

Abstract

Polyphenylene oxides (PPO) of formula (I) are claimed. In (I) and (II) n=20-500 and R1, R2 are 1-20C aliphatic or 6-24C aromatic residue. (I) are produced by reaction of polyphenylene oxides of formula (II) with mono-halo cpds. of formula R-Hal (with R = R2; Hal = Cl, Br or I, pref. Br) in a solvent in the presence of a base. (II) are known PPO as described, e.g. in DE-A 3814166; the reaction is carried out, e.g. in diphenylsulphone (III) in the presence of NaOH or KOH. USE/ADVANTAGE - (I) are useful for the prodn. of moulded prods. (claimed). The invention provides PPO which are thermally stable and stable in soln. (prior-art PPO with Hal or OH end gps. tend to gel in soln. and become insol. in NMP on melting at 290 deg. C. even under nitrogen).

Description

The invention relates to a new, thermally stable Polyphenylene oxide (PPO), a process for its production as well as its use in making molded Body.

The production of polyphenylene oxides from p-halophenols is known, e.g. B. from FR-A 1 301 174, the US-A 3,228,910, 3,491,058, 3,507,832 and 3,455,736 Europ. Polym. Jr. 4, 275 (1968), "High Temperature Resistant Plastics "(Carl-Hanser-Verlag, Munich, 1969) etc.

However, polyphenylene oxides are obtained which are at least a chain end halogen and / or OH groups wear. These connections are thermal and unstable in solution. A solution to this PPO in NMP (NMP = N-methylpyrrolidone) gelled. After melting this PPO at 290 ° C even under nitrogen (5 min) these become insoluble in NMP.

It has been found that polyphenylene oxides with suitable End groups stable both thermally and in solution are.

The invention relates to polyphenylene oxides Formula (I)

wherein
n stands for a number from 20 to 500 and
R¹ and R² are independently C₁-C₂₀ aliphatic or C₆-C₂₄ aromatic radicals.
Preferably R1 and R2 are phenyl.

Another object of the invention is a method for the production of the new polyphenylene oxides of the formula (I)

wherein
n stands for a number from 20 to 500 and
R¹ and R² independently of one another represent C₁-C₂₀ aliphatic or C₆-C₂₄ aromatic radicals,
characterized in that polyphenylene oxides of the formula (II)

in which
n stands for a number from 20 to 500,
with mono-halogen compounds of the formula (III)

R-Hal, (III)

in which
R can stand for the radicals R 1 and R 2 defined in formula (I) and
Hal represents halogen such as Cl, Br, J, preferably Br,
be reacted in a solvent in the presence of a base.

Polyphenylene oxides of the formula which can be used according to the invention (II) are known and described in DE-A 3 814 166.

High-boiling organic solvents can be used as solvents such as sulfones, e.g. B. diphenyl sulfone used will.  

As bases, (earth) alkali hydroxides (e.g. from Na, K) be used.

The polyphenylene oxides of the formula (I) according to the invention show at elevated temperature, e.g. B. at 290 ° C (5 min under nitrogen) and improved stability soluble even after this treatment (e.g. 15% by weight in boiling NMP).

The polyphenylene oxides according to the invention can be used alone or as mixtures with 5 to 95% by weight of other thermoplastics, e.g. B. with other polyaryl (thio) ethers, polyesters, Polycarbonates, polyarylates, polyetherimides, Vinyl polymers, polyamides etc. for the production shaped body can be used.

The polyphenylene oxides according to the invention can also up to 70% by weight of conventional mineral fillers, e.g. B. chalk, silicon dioxide, glass balls, glass powder, Aluminum, clay or fibers such as glass or carbon fibers alone or as mixtures, pigments (e.g. titanium dioxide), thermal stabilizers (e.g. zinc oxide), UV stabilizers, Plasticizers, etc. included.

The polyphenylene oxides according to the invention are used as thermoplastics and can by known methods Fibers, foils, moldings are processed.

Example 1 Production of p-sodium bromophenolate

400.0 g (2.31 mol) of p-bromophenol are added under nitrogen dissolved in 200 ml of methanol. Then 201.3 g (2.26 mol) 45% sodium hydroxide solution added. The mixture is heated and about 200 to 300 ml of methanol / water mixture are distilled off. 500 ml of toluene are added and the remaining water is distilled off azeotropically. p-sodium bromophenolate precipitates. The mixture will cooled and under nitrogen over a G-3 glass filter aspirated. The solid is twice with Washed cyclohexane and dried in a high vacuum at 60 ° C.

The bromophenol used (from Janssen) showed one Bromine content of 46.2% (th. 46.19%).

Production of the PPO according to the invention

84.5 g of diphenyl sulfone are placed in a 500 ml three-necked flask submitted under nitrogen and heated to 150 ° C. At this temperature 100 mg Cu (I) Cl in 6 ml of pyridine added and then to 180 ° C. heated.  

At this temperature, 27.3 g (0.144 mol) of p- Sodium bromophenolate and 0.66 g (4 mole%) sodium phenolate added. It is kept at 195 ° C for 4 hours after cooling to 160 ° C., 4.52 g (20 mol%) are still Bromobenzene was added and the mixture was heated under reflux for two hours. After cooling to 160 ° C from acetone / isopropanol like. The product is suctioned off with distilled Washed water neutral. Then will it in hydrochloric acid methanol (2: 1) at reflux for two hours cooked, washed neutral and dried.

Yield: 10.6 g (81%)
Melting point: 250 ° C

Comparative Example 1 Production of a PPO without chain terminators

84.5 g of diphenyl sulfone are placed in a 500 ml three-necked flask submitted under nitrogen and heated to 150 ° C. At this temperature 100 mg Cu (I) Cl in 6 ml of pyridine added and then heated to 180 ° C. At this temperature, 27.3 g (0.144 mol) p-sodium bromophenolate added. It will held at 195 ° C for four hours.

Refurbishment as in example 2
Yield: 12 g (92%)

Comparative Example 2 Production of a PPO with phenolic chain terminator

The procedure is as in Comparative Example 1, with Difference that an additional 0.99 g (6 mol%) of sodium phenolate added when charging the sodium bromophenolate becomes.

Yield: 9.3 g (71%)
Melting point: 260 ° C

Example 2 Melting tests

1 g each of the polymers from example 1, comparative example 1 and Comparative Example 2 are in a 50 ml flask weighed in and under nitrogen for 5 min 320 ° C hot salt bath. After cooling down the product is crushed and the solubility in hot NMP checked.  

Claims (3)

1. Polyphenylene oxides of the formula (I) wherein
n stands for a number from 20 to 500 and
R¹ and R² are independently C₁-C₂₀ aliphatic or C₆-C₂₄ aromatic radicals. 2. Process for the preparation of the polyphenylene oxides of the formula (I) wherein
n stands for a number from 20 to 500 and
R¹ and R² independently of one another represent C₁-C₂₀ aliphatic or C₆-C₂₄ aromatic radicals,
characterized in that polyphenylene oxides of the formula (II) in which
n stands for a number from 20 to 500,
with mono-halogen compounds of the formula (III) R-Hal, (III) in which
R can stand for the radicals R 1 and R 2 defined in formula (I) and
Hal represents halogen such as Cl, Br, J, preferably Br,
be reacted in a solvent in the presence of a base. 3. Use of polyphenylene oxides according to claim 1 in and / or for the production of shaped bodies.