DE1241995B - Process for the production of polymers - Google Patents

Description

Process for the preparation of polymers From »Journal of the American Chemical Society ", Vol. 82 (1960), pp. 2712 to 2714, it is known that olefinically unsaturated to polymerize tertiary phosphine oxides, resulting in soluble polymers. According to this reference, diallyl and dimethallylphenylphosphine oxides are polymerized.

It is known that allyl compounds show only a slight tendency to Polymerization using free radicals as catalysts, as a termination the chain transfer occurs, which is why, according to this reference, only bad ones Yields of low molecular weight products can be obtained.

Since the polymers obtainable according to this reference are cyclic Contain groups, they are not stable when heated. In view of this is It is completely surprising that, according to the process of the invention, polymers in good yield with extremely advantageous properties as an adhesive and fire retardant can be obtained.

The process according to the invention for the preparation of polymers by polymerization of olefinically unsaturated tertiary phosphine oxides consists in that an olefinically unsaturated tertiary phosphine oxide of the general formula wherein A and A 'denote an alkyl group having 1 to 18 carbon atoms or an aryl group, used alone or in a mixture with other ethylenically unsaturated compounds.

The following is the typical production method of the starting product Described monomers used, for which no protection is claimed in the context of the invention will. Chlorodiphenylphosphine is reacted with ethanol in the presence of triethylamine, whereby the corresponding diphenylethoxyphosphine is formed. This product will then reacted with 1,2-dibromoethane, diphenylvinylphosphine oxide and the By-product triethylamine hydrobromide is obtained.

The reactions for making the monomers can be expressed in the form of equations as follows: íO) PCI t HOC2H, - (43) POC2Hõ> HCI 0 Excess ll / POC2Hõ + BrCHgCH2Br> O PCH2CH2Br + G2H5Br 0 0 oPCH? CHOßI- (CH.) IN + i) 1t3) = CH2 + (G2H5) 3N HBr Typical saturated monohydric alcohols for the preparation of the monomers are the lower alkyl alcohols, such as. B. methanol, methanol, propanol, isopropanol and butanol.

The tertiary amines used to make the monomers are the trialkylamines, such as. B. the tri-lower-alkylamines, pyridine and dimethylaniline.

Organic and inorganic are used to produce the monomers Bases used, which can be strong or weak. Such typical bases are the alkali hydroxides, ammonium hydroxide, the lower alkali alkoxides and tertiary ones Amines of the kind given above.

Of those used as reactants to make the monomers organic halides are given as examples: 1,2-dibromoethane, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, 1-bromo-2-chloroethane, 1,1,2,2-tetrabromoethane and 3,4-dichlorobutene-1.

The polymers and copolymers produced according to the invention are valuable as adhesives and / or as fire retardant polymers.

The preparation of the monomers is explained below: A. Diphenylvinylphosphine oxide To a solution of 27.4 g of ethanol (0.60 mol) and 54.5 g of triethylamine (0.53 mol) In 300 ml of benzene, 109.5 g of chiordiphenylphosphine (0.50 Mol) added. The mixture is at 20 to 30 ° C during the 20 minute addition period and is stirred at room temperature for an additional 2 hours. Triethylamine hydrochloride is formed and removed by filtration and the resulting mixture fractionated distilled. An 87 weight percent yield of 98.85 g of diphenylethoxyphosphine is obtained, bp 121 each at 0.7 mm mercury pressure.

Analysis: (C14H, 5OP) Calculated. . C 73.0 ° / o, H 6.520 / 0, P 13.47 ° / o; Found ... C 73.21 ° / o, H 6.630 / o, P 13.330 / 0.

In an excess of 1440 g of 1,2-dibromoethane (7.62 mol) slowly 86.0 g of diphenylethoxyphosphine (0.374 mol) were added. The mixture becomes reflux brought under a 45.72 cm silver-plated, packed with glass snakes and with Vacuum jacketed column. Ethyl bromide is formed and to the extent of its formation removed.

No further ethyl bromide is observed after 2 hours. Excess 1,2-dibromoethane is removed by distillation, and cumene (which acts as a "scavenger" acts) is added to remove the last traces of ethyl bromide. The finally The reaction mixture obtained is a mixture of 2-bromoethyldiphenylphosphine oxide in cumene.

This mixture is diluted with 300 ml of toluene.

To this end, 42.0 g of triethylamine (0.415 mol) are slowly added with stirring. There is no evolution of heat, nor is any salt immediately visible. On refluxing for 11½ hours, a large amount of salt appears. In addition, 5.0 g of triethylamine in 100 ml of toluene are added to ensure a complete Ensure response. After a further 2 hours under reflux, the solution becomes cooled down and the held triethylamine hydrobromide filtered off. Something of that Product comes out of solution at this point and is later recovered. The main amount of the product is obtained by reducing the toluene volume by distilling off, Dilute with heptane and cool. A total yield of 60.8 g of diphenylvinylphosphine oxide is obtained, m.p. 116.5 to 118 "C. This is a yield of 71.5 percent by weight, based on the diphenylethoxyphosphine reactant, and from 62 "10, based on the chlorodiphenylphosphine reactant.

Analysis: (C14H130P) Calculated ... C 73.90 / 0, H 5.700 / 0, P 13.60 / o; found C 73.60 / 0, H 6.20%, P 13.80 / o.

Iodine number: calculated 111.5, found 109.5.

The tertiary phosphine oxides used according to the invention are homopolymerized or with ethylenically unsaturated compounds, such as. B.

Styrene, methyl methacrylate, acrylonitrile, vinyl chloride, vinyl acetate and ethylene, copolymerized.

The polymerization is effected by common means among Use of a polymerization catalyst, such as. B. di-tert-butyl peroxide, benzoyl peroxide or azobisisobutyronitrile. In general, the reaction takes place in the presence of a Solvent, such as. B. aromatic hydrocarbon instead. Typical examples are benzene, toluene or xylene.

The following examples serve to illustrate the invention.

Example 1 A mixture of 2.13 g of diphenylvinylphosphine oxide and 0.02 g of di-tert-butyl peroxide is placed in a thick-walled tube, which twice has been degassed at -78 "C. The tube is sealed under vacuum and heated to 1353C heated. The liquid mixture becomes glassy in about 24 hours at this temperature. After 48 hours of heating at this temperature, the thick-walled tube is opened and their contents dissolved in chloroform and precipitated in heptane. The infrared analysis shows no vinyl units. The intrinsic viscosity of this material, which in alcohol containing 20/0 benzene at 30 "C using a Cannon-Ubbelohde semi-micro-dilution viscometer was determined, [n] = 0.02. The average molecular weight of the in the homopolymer material produced in the manner just described is 1348, such as was determined by the usual microanalysis method.

Example 2 The procedure of Example 1 was repeated and the results obtained are shown in the table below. weight Diphenylvinyl weight of product after 24 hours conversion to further basic molecular molar phosphine oxide di-tert-butyl peroxide long heating at 130-C heating weight viscosity number gg [n] 1 0.036 immovable glass 1000/0 after 36 hours 692 I 0.02 1 0.036 highly viscous liquid 100% after one week - - 2.2 j 0.036 immovable glass 100010 after 36 hours 1,348 0.02 Example 3 A mixture of 1 g of diphenylvinylphosphine oxide, 1 g of styrene, 0.010 g of azobisisobutyronitrile and 3 ml of benzene was placed in a thick-walled tube which was degassed at -78 "C and sealed under vacuum. The mixture was then stored for 6 days at 60" C heated. At the end of this period the tube was opened and the liquid filtered. The residue contained 0.1 g of diphenylvinylphosphine oxide.

The benzene solution forming the filtrate was added to methanol and the precipitated polymer (0.58 g) recovered. The polymer had a Intrinsic molar viscosity at 30 "C of [12J 0.155 and contained 3.040 / 0 phosphorus. This corresponds to a molar ratio of phosphine oxide to styrene in the polymer of 0.13 compared to 0.50 in the original feed.

The polymer melted but did not burn on exposure to the opposite an open flame.

Example 4 The procedure of Example 3 was repeated using of 1 g of diphenylvinylphosphine, 3 g of methyl methacrylate, 0.010 g of azobisisobutyronitrile and> ml of benzene. The precipitation in methanol gave 0.55 g of a polymer (A) received.

The filtrate obtained from the removal of the polymer (A) was distilled to remove the volatiles including the solvents, and a viscous oil was obtained, which was dissolved in chloroform and precipitated in benzene, whereby 0.45 g of a polymer ( B) were obtained. Both polymers melted, but did not burn upon exposure to an open flame. The properties of the polymers are given below: Basic molar molar ratio Poly viscosity number / 0 poly diphenylvinylphosphine oxide merisat at 309C merisat to methyl methacrylate Polymer feed A 0.32 1.45 0.483 0.051 B 0.08 5.26 0.483 0.275 B. Diisobutylvinylphosphine oxide According to A, 27.7 g of ethanol (0.60 mol), 60.5 g of triethylamine (0.60 mol) in 400 ml of benzene and 97.5 g of chlorodiisobutylphosphine (0.50 mol) were reacted. 125.8 g of diisobutylethoxyphosphine, boiling point 103 ° C./39 mm Hg to 98 ° C./2 mm Hg, were obtained.

The product obtained became an excess of 1300 g of 1,2-dibromoethane (6.95 mol) was added to give the compound (isobutyl) .P (O) CH2Cfl2Br. This product was dehydrobrominated according to A. A total of 21 g (isobutyl) 2P (O) CH = CH2 obtained, bp 122 to 123 "C / 8mm, F. = 18" C.

Example 5 Monomer B was prepared according to the procedure of Example 1 polymerized to a polymer, which is excellent against an open flame Fire resistance possessed.

Claims (1)

Claim: Process for the production of polymers by polymerizing an olefinically unsaturated tertiary phosphine oxide, characterized by the fact that an olefinically unsaturated tertiary phosphine oxide of the general formula is used in which A and A 'denote an alkyl group having 1 to 18 carbon atoms or an aryl group, used alone or in a mixture with other ethylenically unsaturated compounds. Papers considered: Journal of the American Chemical Society, 82 (1960), pp. 2712-2714.