DE1203952B - Process for vulcanizing halogenated butyl rubber or polychloroprene - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

C08f

German KL: 39 b -22/06

Number: 1203 952

File number: E 25579IV c / 39 b

Filing date: September 24, 1963

Opening day: October 28, 1965

The subject of the invention is a method for vulcanizing of halogenated butyl rubber or of polychloroprene using sulfur-containing vulcanizing agents, characterized in that the vulcanizing agent used is 0.1 to 10 percent by weight on the polymer, on trithiocyanuric acid or trithiane, optionally in a mixture with a stannous or zinc compound is used.

It is known that halogenated rubbers of the types described above can be used with certain Metal oxides, especially zinc oxide, can vulcanize. This applies to chlorinated butyl rubber, and the mechanism of implementation is provided by Baldwin and his co-workers in “Rubber and Plastics Age ", p. 42 (1961).

It is also a vulcanization of halogenated butyl rubber with mercaptobenzothiazole or its Known derivatives. However, this known vulcanization only works at elevated temperatures of 66 up to 232 ° C in front of you.

The vulcanization according to the invention has the opposite of the known vulcanization with mercaptobenzothiazole the particular advantage that they are not only at elevated temperatures, but also at room temperature can be carried out. The trithiocyanuric acid can by itself, but preferably can be used together with a stannous compound such as stannous chloride. The additional amounts of the Trithiocyanuric acid range between 0.1 and 10, prior to the process of vulcanizing halogenated Butyl rubber or polychloroprene

Applicant:

Esso Research and Engineering Company, Elizabeth, N.J. (V. St. A.)

Representative:

Dipl.-Chem. Dr. jur. W. Beil, A. Hoeppener and Dr. H. J. Wolff, lawyers, Frankfurt / M.-Höchst, Adelonstr. 58

Named as inventor:

Henry Alfred Cook, Didcot, Berkshire; Eric Bannister,

Blewbury, Berkshire (UK)

Claimed priority:

Great Britain, September 25, 1962 (36389), October 26, 1962 (40545)

preferably 0.15 and 5 parts by weight to 100 parts by weight Rubber.

Examples 1 to 9

A series of experiments at room temperature with vulcanizates, trithiocyanuric acid and stannous chloride or trithiocyanuric acid and zinc oxide are given in Table I. Example # 5 represents one Comparative experiment.

Table I.

Addition of trithiocyanuric acid to chlorobutyl rubber. Vulcanization at normal temperature

1 2 3 4th Example
5 1
6th _7th 8th Q Composition (parts by weight)
Chlorobutyl rubber 100
50 100
50 100
50 100
50 100
50 100
50 100
50 100
50 100
50 Soot.; 1 1 1 1 1 1 1 1 1 Stearic acid 0.5 0.5 1 1 2 2 Stannous chloride 0.5 - 1 0.25 0.5 C. 5
4th Zinc oxide Trithiocyanuric acid

509 719/446

Table I (continued)

2 3 4th example 6th 7th 8th 9 1 4.2 4.9 4.9 5 33.8 30.2 4.2 4.2 4.2 4.2 4.9 4.9 7.2 29.5 40.8 4.9 5.6 4.2 4.2 16.9 4.9 11.9 - - - - 4.2 5.6 14.8 12.7 15.5 44.3 47.8 - - 4.2 - - - - - - 16.9 19.7 9.8 21.0 15.5 - 52.7 42.2 9.1 11.9 4.2 - - - 37.3 - - 9.1 12.7 11.9 26.0 21.1 - - - 11.2 14.1 9.3 -

Tensile strengths (kg / cm ² )

After 1 day

After 2 days

After 3 days

After 4 days

After 7 days

After 8 days

After 9 days

After 11 days

From the tensile strength values in Table I it can be seen that self-vulcanization is a minimum amount of 0.5 part of trithiocyanuric acid and 1.0 part of stannous chloride to 100 parts of rubber (Example 3) requires that, however, even with such a small amount, ao as 0.25 part of trithiocyanuric acid, a considerable amount Acceleration can be determined if the amount of stannous chloride is reduced to 2.0 parts per 100 parts of rubber increased. It can be seen that after one day the vulcanizate of Example 6 has a tensile strength which is more than four times as high as that of a vulcanizate (Example 5), in which 2.0 parts alone Stannous chloride per 100 parts of rubber came, but no trithiocyanuric acid. Stannous chloride alone is in able to vulcanize chlorinated butyl rubber at normal temperature, but only very slowly, on the other hand, combinations of trithiocyanuric acid with the commonly used zinc oxide vulcanize also only very slowly at normal temperature.

Examples 10 to 13

Table II shows a series of experiments in which trithiane with the following structural formula

CH ₂

S S

CH ₂ CH ₂

was used as an additive in place of trithiocyanuric acid. Suitable amounts of trithiane are between 0.1 and 10, preferably 1 to 5 parts by weight per 100 parts by weight of the rubber.

Table II Trithian as an additive for self-vulcanization

example

11

12th

13th

Composition (parts by weight)

Chlorobutyl rubber

soot

Stearic acid

Trithian

Zinc oxide

Stannous chloride

Zinc chloride

Tensile strength (kg / cm ² )

After 3 hours at normal temperature

After 1 day at normal temperature

After 2 days at normal temperature

After 3 days at normal temperature

After 4 days at normal temperature

After 5 days at normal temperature

After 8 days at normal temperature

It can be seen that considerable self-vulcanization is caused by the addition of Trithians and Zinc chloride is achieved that it occurs only very slowly or not at all with stannous chloride.

Examples 14-17, 18-23

In a further series of experiments in which the masses at elevated temperature (153 ⁰ C) vulkani-100

50

7.7
25.3
28.9
33.0
23.9
39.4
42.2

100
50

1
4th
4th

7.0
23.2
26.0
29.6
28.9
36.6
35.9

100

4.9 4.9 4.9 4.9 4.9 4.9 4.9

100 50 1 4 4 1

6.3

6.3

7.7

10.5

11.9

19.0

15.5

were sated, the mixtures mixed with trithiocyanuric acid showed reduced elongation and an increasing hardness. In the case of trithiane, vulcanization at elevated temperature gave improved results Tensile strength and better elongation modules of the products compared to vulcanization with zinc oxide alone, and compression set properties were also good. The results of these experiments with trithiocyanuric acid and trithiane as hardening

medium at 153 ^° C. are compiled in Table III and Table IV. It should be pointed out that particularly good compression set (15.9%) ^and good tensile strength (160 kg / cm ² ) together with adequate elongation by adding 2 parts of trithiane to 100 parts of rubber after a vulcanization time of only 10 minutes. The vulcanization is also very "flat". It is particularly noteworthy (Example 23 in Table IV) that the trithiane does not vulcanize under the test conditions without zinc oxide. Example No. 14 represents a comparative experiment, as is Example No. 18.

Table III 1. Vulcanization with addition of trithiocyanuric acid

14th

example
I 16

17th

Chlorobutyl rubber

soot

Antioxidants

Trithiocyanuric acid

Zinc oxide

100 50

1
4th
5

Physical Properties

example

14th

15th

Vulcanization time under pressure at 153 ⁰ C, minutes

Tensile strength, kg / cm ²

Elongation, ° / ₀

module

100% kg / cm ²

200% kg / cm ²

300% kg / cm ²

400% kg / cm ²

According to Shore A hardness

Scorch resistance test MS at 127 ° C,

increase

20th
94.8
350

15.5
45.7
78.8

64

106.2 320

20.4 59.0 94.2

none within minutes

Physical Properties

example

16

17th

Vulcanization time under pressure at 153 ° C, minutes

Tensile strength, kg / cm ²

Strain, %

module

100% kg / cm ²

200% kg / cm ²

300% kg / cm ²

400% kg / cm ²

According to Shore A hardness

Scorch resistance test MS at 127 ° C, increase

10
80.2
380

18.3
40.8
60.4

20th
89.2
330 40
111.1
310 10
91.4
320 20th
102.7
310 18.3
44.3
82.9 23.4
63.3
104.0 23.4
54.1
84.4 26.7
61.1
99.0 66 68 68 68 te in 0.4 minutes 5 points in 0.8 Ϊ

111.1 200

30.2 74.5

Table IV 2. Vulcanization with added trithiane

19th example 20th 21 22nd 18th 100 100 100 100 100 50 50 50 50 50 1 1 1 1 1 5 5 5 5 5 1 1 1 1 ι 0.5 1 2 4th - -

Chlorobutyl rubber

soot

Antioxidants

Zinc oxide

Stearic acid

Trithian

100

50

Table IV (continued)

Physical Properties

example

18th 10
123.8
420 20th
123.8
410 40
118.1
430 60
121.6
400 19th 10
114.6
300 20th
131.5
320 40
133.6
330 8.4
38.7
80.2
115.3 9.8
38.7
80.2
118.1 9.1
34.5
74.5
110.4 8.4
40.1
16.0 16.9
59.8
109.7 17.6
61.2
112.5 16.2
57.7
126.6 34.6 15.2 11.4 13.5 31.4 10.9 7.4 10 5

Vulcanization time under pressure at 153 ⁰ C, minutes

Tensile strength, kg / cm ²

Strain, %

module

100% kg / cm ²

200% kg / cm ²

300% kg / cm ²

400% kg / cm ²

Compression set ASTM D 395-55, method B,

22 hours at 7O ⁰ C,%

Scorch resistance test MS at 127 ⁰ C,

Minutes to an increase of 5 points

Physical Properties

example

20th

21

Vulcanization time under pressure at 153 ° C, minutes

Tensile strength, kg / cm ²

Strain, %

module

100% kg / cm ²

200% kg / cm ²

300% kg / cm ²

400% kg / cm ²

Compression set ASTM D 395-55, method B,

22 hours at 70 ⁰ C,%

Scorch resistance test MS at 127 ⁰ C,

Minutes to an increase of 5 points

20th
135.7
310 40
137.1
300 60
140.6
280 10
157.5
300 20th
139.2
220 40
140.6
280 18.3
69.6 20.4
75.2 22.5
73.2 23.9
90.7 25.3
87.2 26.7
84.4 11.0 6.9 8.5 15.4 9.5 8.1 4th 3

Physical Properties

example

22nd

23

Vulcanization time under pressure at 153 ° C, minutes

Tensile strength, kg / cm ²

Strain, %

module

100% kg / cm ²

200% kg / cm ²

300% kg / cm ²

400% kg / cm ²

Compression set ASTM D 395-55, method B,

22 hours at 70 ⁰ C,%

Scorch resistance test MS at 127 ° C ₃

Minutes to an increase of 5 points

20th

128.7
250

31.6 33.7
110.4 99.8

9.3

40

138.5
250

31.6
101.9

7.5

60

144.1
259

31.6
104.1

10.1

10
5.6
1100

20th
7.0
1100

40
14.1
600

60
9.1 7.00

no increase within
of 30 minutes

Claims (1)

Claim: Process for vulcanizing halogenated butyl rubber or polychloroprene by sulfur-containing vulcanizing agents, thereby characterized in that 0.1 to 10 percent by weight, based on the vulcanizing agent the polymer, of trithiocyanuric acid or trithiane, optionally mixed with a stannous egg Zinc compound, can be used. Considered publications:
U.S. Patent No. 2,992,202. 509 719/446 10.65 © Bundesdruckerei Berlin