DE1268845B - Process for the production of vinyl chloride-vinylidene chloride copolymers - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C08f

German class: 39 c - 25/01

Number: 1268 845

File number: P 12 68 845.8-44

Filing date: May 12, 1965

Open date: May 22, 1968

Films, tubes and other molded articles made from copolymers of vinylidene chloride and vinyl chloride are preferred because of their superior properties used as packaging materials for food.

For reasons of hygiene, certain types and amounts of catalysts and other additives are used in the processing of the copolymers or in the course of the polymerization can only be used to a limited extent. Especially in the suspension copolymerization of vinylidene chloride and vinyl chloride influence the properties of the catalysts to a great extent Toxicity, color and certain thermal and mechanical properties of the copolymer obtained and the molded body obtained therefrom.

So far, one has for the copolymerization of vinylidene chloride and vinyl chloride in general Azo compounds, ζ. B. azobisisobutyrolonitrile, or peroxides, e.g. B. benzoyl peroxide, octanoyl peroxide or Lauroyl peroxide, used as catalysts. The smell, the toxicity and certain thermal and mechanical properties of the molded bodies produced from copolymers obtained in this way, however not completely flawless. Smaller ones can be used to improve these properties Use some catalyst amounts, but this generally increases the rate of polymerization is greatly reduced and consequently becomes too long for the industrial production of these copolymers.

For the polymerization of vinyl compounds, especially vinyl chloride, in aqueous suspension In the presence of suspension stabilizers, the use of alkyl peroxydicarboxylates continues known as catalysts that have greater activity. So you can with diisopropyl peroxydicarbonate the monomers polymerize rapidly even at a relatively low polymerization temperature. However, this catalyst is used for Manufacture of copolymers of vinylidene chloride and vinyl chloride used in the manufacture of packaging materials to serve for food, not suitable because an unpleasant odor remains in the resin. As was further found Butoxyethyl peroxydicarbonate is a non-toxic catalyst, but its odor is not perfect. In addition, the half-life of the decomposition of the catalyst is too short, even at low temperatures, so that there is a problem of safe handling.

A process for the production of vinyl chloride / vinylidene chloride copolymers has now been established Process for the production of vinyl chloride-vinylidene chloride copolymers

Applicant:

Kureha Kagaku Kogyo Kabushiki Kaisha, Tokyo

Representative:

Dr.-Ing. W. Reichel, patent attorney,

6000 Frankfurt 1, Parkstr. 13th

Named as inventor:

Yasuo Amagi,

Zenya Shiiki, Nakoso-Shi (Japan)

Claimed priority:

Japan May 14, 1964 (27 097)

by polymerizing a mixture of vinyl and vinylidene chloride in aqueous suspension, in the presence of suspension stabilizers and diesters found the peroxydicarboxylic acid as polymerization catalysts, in which the above Disadvantages of the known processes are avoided when the peroxydicarboxylic acid is used as a diester Compounds of the general formula

O O

Cl- (CH ₂ ) "- OCOOCO- (CH ₂ ) _m -Cl

where η and m S; 2 are to be used.

Compared to the toxicity, the odor and the thermal stability of a copolymer that with the usual catalysts, e.g. B. benzoyl peroxide, lauroyl peroxide, azobisisobutyronitrile, peracid esters, Isopropyl peroxydicarbonate, etc., result with the method of FIG Catalysts used in the invention are copolymers, the moldings with superior properties deliver. In addition, even a small amount of the catalysts used according to the invention can be used cause sufficiently rapid polymerization for industrial purposes.

The catalysts of the general formula mentioned in which m and n are used in the process of the invention are preferably in the range from 2 to 5

809 * W «5

IO

can be made from sodium peroxide and the corresponding chloroformic acid ester of the formula

Il

Cl- _(CH2) ,, - O - C - CI

in turn by the reaction of phosgene with the corresponding chlorohydrin

Cl- (CH ₂ ) "- OH

has been obtained, has been produced.

4-chlorobutyl peroxydicarbonate can e.g. B. have been prepared in the following manner: A glass bottle of 500 cm ³ capacity, which is equipped with a stirrer, a dropping funnel and a reflux condenser, which is cooled by circulating methanol, which is saturated with dry ice, is with 101 g of liquid Phosgene filled; then 85 g of 4-chlorobutanol-1 are added dropwise at the boiling point of phosgene while the mixture is stirred. After 3 hours, the reaction is terminated and the excess phosgene is blown out by introducing gaseous nitrogen into the reaction mixture. The residue left in the bottle is almost pure 4-chlorobutyl chloroformate, the yield of which is 94%.

The 4-chlorobutyl chloroformate obtained is then cooled to a temperature of 0 to 5 ° C., and 700 cm ^{3 of} an aqueous solution containing 50 g of sodium peroxide and cooled to the same temperature are then added dropwise with vigorous stirring. After stirring for 2 hours, the oily phase of the reaction mixture is separated off, washed several times with cold water and then dried over anhydrous sodium sulfate. 4-chlorobutyl peroxydicarbonate is obtained with a yield of 75% and a purity of 98.5%.

The various properties of the catalysts used according to the invention, namely toxicity (lethal dose LD ₅₀ ), half-life of disintegration and tendency to explode, are given in the table below. For comparison, information about diisopropyl peroxydicarbonate, butoxyethyl peroxydicarbonate, azobisisobutyronitrile and lauroyl peroxide are also given:

catalyst 2 2 O 2 -> O
Η 2 Poison
LD ₅₀ ¹ ) opportunity
LD ₅₀ -) odor Half-life
of decay
55 ° C in hours Explosion
Tilt
in minutes ³ ) C ₄ H ₉ -OC ₂ H ₄ -OCO- Q ₁ H ₂₃ -CO 2 CN
CH _3x I.
J) CN- 0.4 0.3 very weak 5.7 none ⁴ ) 2 1.5 0.8 very weak 4.0 no 5.2 3.7 very weak 4.3 no 1.0 0.7 strong 2.8 15th 4.0 3.1 weak 1.1 5 0.2 0.02 weak 15th no - - . weak 55 no O
H Il
Cl (CH ₂ ) ₂ OCO 0
It Cl- (CH ₂ J ₃ —O - C— O - ' O
π Cl- (CH ₂ J ₄ -OCO- O CH ₃ ν II
; ch — o — c —o -
CH ₃ /

') Mean lethal dose of the catalyst for rats.

² ) Mean lethal dose of the catalyst decay products for rats.

³ ) Time to explosion at 30 C. *) Not explosive.

example 1

A stainless steel autoclave with a capacity of 100 liters and equipped with a stirrer is filled with 40 liters of water containing 80 g of methyl cellulose, and then, after purging several times with nitrogen, 16 kg of vinylidene chloride containing 40 g of 4-chlorobutyl peroxydicarbonate are added. and 4 kg of vinyl chloride added. The polymerization takes place at 50 ^; C for 40 hours. 84 percent by weight of the monomers introduced are converted into a copolymer which remains colorless even when heated.

Example 2

In the same way as in Example 1, the polymerization is carried out using 40 g of 3-chloropropyl peroxydicarbonate as a polymerization catalyst. From the introduced monomers 78.5 percent by weight converted into a copolymer that has almost no odor.

Claims (2)

Patent claims: 1. Process for the production of vinyl chloride-vinylidene chloride mixture polymers by polymerizing a mixture of vinyl and vinylidene chloride in aqueous suspension in the presence of suspension stabilizers and diesters of peroxydicarboxylic acid as polymerization catalysts, characterized in that compounds are used as diesters of peroxydicarboxylic acid the general formula Cl - (CH ₂ ), -OCOO - C- O- (CH ₂ ) _m -Cl where η and m ^ 2 are used. 2. The method according to claim 1, characterized in that compounds of the general formula according to claim 1 in which the sizes η and m are in the range from 2 to 5 are used. Considered publications:
U.S. Patent No. 3,022,282. MM »0/465 5.6S Ο Bundesdruckerci Berlin