Bis-hydrazone antiozonants and rubber compositions
Document Number
GB Patent 953909
Publication Date
1964-04-02
Link
Inventors
not available
Abstract
Abstract of
GB953909
The invention comprises terephthalaldehyde bis (di-n-butylhydrazone), glyoxal bis (di-n-butylhydrazone), glutaraldehyde bis (di-n-butyl-hydrazone) and the preparation thereof by reacting 1, 1-di-n-butylhydrazine with terephthalaldehyde, glyoxal and glutaraldehyde respectively.ALSO:Natural and synthetic rubbers are protected against ozone deterioration by the inclusion of from 0.1 to 5% by weight of a bis-(hydrazone) of the formula: <FORM:0953909/C3/1> or <FORM:0953909/C3/2> wherein n is 0 to 8, R1, R2 and R3 independently represent aralkyl, aryl, straight, branched or cyclized alkyl, alkenyl, hydroxyalkyl or alkoxyalkyl radicals having from 1 to 18 carbon atoms, or R3 may additionally represent a hydrogen atom and R1 and R2 together may additionally represent a dimethylene, tetramethylene, pentamethylene, hexamethylene or oxydiethylene radical.
Nouvelles hydrazones et leur application comme agents anti-ozone
Inventor:
Applicant: US RUBBER CO
EC:C07C109/14; C07C109/16; (+3)
IPC: C07D295/30; C08K5/30; C11B5/00(+3)
Publication info: FR1297001 A - 1962-06-22
2
Bis-hydrazone antiozonants and rubber compositions
Inventor:
Applicant: US RUBBER CO
EC:C07C109/14; C07C109/16; (+4)
IPC: C07D295/30; C08K5/30; C09K15/16(+5)
Publication info: GB953909 A - 1964-04-02
3
No title available
Inventor:
Applicant:
EC:C07C109/14; C07C109/16; (+4)
IPC: C07D295/30; C08K5/30; C09K15/16(+5)
Publication info: LU40518 A1 - 1961-10-18
4
No title available
Inventor:
Applicant:
EC:C07C109/14; C07C109/16; (+4)
IPC: C07D295/30; C08K5/30; C09K15/16(+5)
Publication info: NL270529 A - 0000-00-00
5
Diolefin polymer rubber stabilized with bis
Inventor: STEWART HUGH W
Applicant: US RUBBER CO
EC:C07C109/14; C07C109/16; (+4)
IPC: C07D295/30; C08K5/30; C09K15/16(+5)
Publication info: US3142658 A - 1964-07-28
List of citing documents
Claims
WHAT WE CLAIM IS:-
1. A diolefin polymer rubber composition containing from 0.1% to 5% by weight of a bis-(hydrazone) antiozonant having the formula:953,909 t'P-1 3. R3A( >N-N= ':---) CHCN=N-N (1), PL CWHN-N< kz wherein n is 0 to 8, R1, R2 and R3 may be the same or different and represent aralkyl, aryl, straight, branched and cyclized alkyl, alkenyl, hydroxyalkyl or alkoxyallkyl radicals 5 having from 1 to 18 carbon atoms, in which R, may also represent a hydrogen atom, and in which R1 and R2 together may additionally represent a dimethylene, tetramethylene, pentamethylene, hexamethylene or oxydiethylene radical.
2. A composition as claimed in claim 1 which is vulcanized.
3. A composition as claimed in claim 1 substantially as described in the foregoing 10 specific description.
4. A method of making a composition as claimed in claim 2 which method comprises intimately mixing the diolefin rubber in its unvulcanized state with the bis(hydrazone) antiozonant, and vulcanising the resulting mixture.
5. A method as claimed in claim 4 substantially as described in the foregoing 15 specific description.
6. Terephthalaldehyde bis-(di-n-butylhydrazone).
7. Glyoxal bis-(di-n-butylhydrazone).
8. Glutaraldehyde bis-(di-n-butylhydrazone).
9. A method of making the compound as claimed in any one of claims 6, 7 20 or 8, substantially as described in any one of the foregoing examples.
T. A. CLAYTON, Agent for the Applicant.
Leamington Spa: Printed for Her Majesty's Stationery Office, by the Courier Press (Leamington) Ltd.-1964. Published by The Patent Office, 25 Southampton Buildings, London, W.C.2, from which copies may be obtained.
Description
PATENT SPECIFICATION
a t" NO DRAWINGS 953,909 . i Date of Application and filing Complete Specification: July 19, 1961.
n 7 i No. 26111/6 1.
11:))i Application made in United States of America (No. 64982) on Oct. 26, 1960.
: Complete Specification Published: April 2, 1964.
Crown Copyright 1964.
Index at acceptance:-C2 C(2A1, 2A2, 2T17, 2T22); C3 P(2C8B, 2C17, 2D1A, 2DIB, 2K7, 2K8, 2Kll, 2T2A); C3 Q5X International Classification:-C 07 c (C 08 c, d) COMPLETE SPECIFICATION
Bis-Hydrazone Antiozonants and Rubber Compositions We, UNITED STATES RUBBER COMPANY, of Rockefeller Center, 1230 Avenue of the Americas, New York, State of New York, United States of America, a corporation organized and existing under the laws of the State of New Jersey, United States of America do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly 5 described in and by the following statement:-
This invention relates to rubber compositions.
This invention consists in a diolefin rubber composition containing from 0.1% to 5% by weight of a bis-(hydrazone) antiozonant having the formula: P, R3 a P-, > - -N=C- (CH2)NC=N-HN 10 (0).
Rz oR, R oCHC=N-N< >-N =CHAD \R? wherein n is 0-8, R1, R2 and R3 may be the same or different and represents aralkyl, aryl, straight, branched and cyclized alkyl, alkenyl, hydroxyalkyl or alkoxyalkyl radicals having from 1 to 18 carbon atoms, in which R3 may also represent a hydrogen atom, 15 and in which R, and R, together may additionally represent a dimethylene, tetramethylene, pentamethylene, hexamethylene or oxydiethylene radical. In formula II the group on the aromatic ring may be in either the o, m, or p position.
The rubber stock to which the ozone inhibitors are added may be any vulcanizable rubber which is ordinarily subject to attack by ozone whether natural (Hevea) rubber, or 20 a synthetic rubber, such as the rubbery homopolymers or copolymers of butadiene and [Price similar aliphatic conjugated diolefin hydrocarbons, such as butadiene-styrene copolymer rubber, butadiene-acrylonitrile copolymer rubber, butadien-vinylpyridine copolymer rubber, isobutylene-isoprene copolymer rubber, and the like. Natural rubber and synthetic rubbers of the foregoing type may be designated by the general term diolefin polymer rubbers. Generally, about 1/10 to 5 parts by weight of the inhibitor per 5 parts by weight of vulcanized diolefin polymer rubber may be employed.
The rubber stock may be compounded with any desired conventional vulcanizing agents, accelerators, softeners, fillers, etc. The compounded rubber stock containing the present inhibitors may be shaped and vulcanized in any desired manner in accordance with conventional practice. Standard test methods reveal in a striking manner 10 the remarkable improvement in ozone resistance imparted to the vulcanizate by the present chemicals.
A method for evaluating the protective ability of antiozone chemicals for inhibiting the ozone deterioration of SBR and other elastomeric materials has been developed by Delman, Simms and Allison, Anal, Chem., 26, 1589 (1954). It is referred to 15 here as the Delman Viscosity Test. It utilizes the rate of change in viscosity of polymeric solutions during exposure to ozone as a criterion for such evaluation. It provides a simple, rapid and reliable means for screening large numbers of chemicals for suitability as antiozonants without resorting initially to vulcanizate preparations which are sometimes complicated by compounding and processing variables. Two modifications were made by us, (a) ozonized air instead of ozonized oxygen was used and (b) synthetic rubber, such as the rubbery homopolymers or copolymers of butadiene and with ozonized air were about the same as those with ozonized oxygen. The higher concentration of ozone gave a mnore accelerated test. The concentration of the test compound was 103( of the rubber polymer. The data given in Table I show 25 the ozone protection given by these compounds. The greater the percentage retention of the initial relative viscosity the greater the ozone protection.
TABLE I
Delman Viscosity Test for Antiozone Chemicals Percent Relative Viscosity Test Compound 1 hr. 2hr. 3hr. 4hr. 5hr. 6hr.
Unprotected SBR 32.7 15.2 - - - Glyoxal bis(dimethylhydrazone) 88.8 79.4 65.3 40.6 19.4 2,4-Pentanedione bis(dimethyl hydrazone) 82.2 59.9 44.6 28.7 16.3 Glutaraldehyde bis(dimethylhydrazone) 93.7 88.4 76.7 59.3 36.0 19.6 Glyoxal bis(di-n-butylhydrazone, 87.5 67.8 47.4 24.3 23.0 11.2 Glutaraldehyde bis(di-nbutylhydrazone) 87.4 74.8 66.9 38.4 18.5 Terephthalaldehyde bis(din-butylhliydrazone) 88.1 72.3 55.4 38.4 23.1 Some of these compounds have been tested as antiozonants in sulphur vulcanized natural rubber white stock. The stocks were compounded according to the following 30 formula:
953,909 953,909 Component Pale crepe Zinc oxide Lithopone Snowflake whiting Zinc salts of coconut oil acids Sulfur Tetramethylthiuram monosulfide Test compound Parts by Weight 100.00 10.00 60.00 60.00 0.50 3.00 0.15 3.00 to 5.00 The stocks were cured for 30 min. at 274 F. For the static tests, 1" x 4" x 3/32" strips were formed into a 2" loop and exposed to 50 pphm. of ozone at 100 F.
in the Mast ozone box and to outdoor weathering on a rack placed 45 degrees to the horizontal. For the dynamic tests, molded stocks 1" x 6" x 1/4" having a 1/8" round groove across center were split into 1/2" wide pieces, mounted outdoors and flexed through a 78 degree angle at about 8.5 kilocycles/hr. The results of these tests are shown in Tables II, III and IV, respectively. The degree of cracking was determined according to an arbitrary scale of measuring, using numerals 1, 2, 3 and 4 to represent cracks which were very fine, fine, medium and coarse (beyond practical use), respectively.
TABLE II
Mast Ozone Box Test Pts./100 R.H.C.
Test Compound Hours to Degree of Cracking 1 2 3 4 Blank 2 36 Glutaraldehyde bis(dimethylhydrazone) 5 60 84 Blank 3 5 Glutaraldehyde bis(di-n-butylhydrazone) 3 3 5 12 34 TABLE III
Outdoor Static Test Days to Degree of Cracking Pts./100 Test Compound R.H.C. 1 2 3 4 Blank 26 41 Glutaraldehyde bis(dimethyl(hydrazone) 5 71 78 112 Blank 6 8 12 Glutaraldehyde bis(di-n-butylhydrazone) 3 51 65 84 953,909 TABLE IV
Outdoor Dynamic Test Kilocycles to Degree of Cracking Pts./100 Test Compound R.H.C. 1 2 3 4 Blank 5 1158 2261 Glutaraldehyde bis(di-methylhydrazone) 5 1158 2261 Blank 865 994 Glutaraldehyde bis(di-n-butylhydrazone) 3 994 1165 1511 The expression "R.H.C." in the above tables means "rubber hydrocarbon" T.A.C.
Some of these compounds are volatible and are partly lost from the rubber stock during cure and on standing. Their effectiveness as antiozonants in cured rubber, therefore, is substantially lessened. More of the less volatile compounds is retained in the rubber during milling and curing and, hence, such compounds are preferred 5 from a practical standpoint.
The new compounds described in Examples 1-3 gave correct analyses for carbon, hydrogen and nitrogen.
EXAMPLE 1
Terephthalaldehyde Bis(di - n - butylhydrazone) 10 To a solution of 9.0 g. (0.07 mole) terephthalaldehyde in 50 ml. benzene was slowly added 22.0 g. (0.16 mole) 1,1-di-n-butylhydrazine. The reaction mixture was heated to the refluxing temperature and the water produced was removed by azeotropic distillation. After removal of the benzene the residue was crystallized from ethanol; m.p. 57-593C. 15 EXAMPLE 2
Glyoxal Bis(di - n - butylhydrazone) To 57.8 g. (0.4 mole) of 1,1-di-n-butylhydrazine was slowly added 38.6 g.
(11.6 g. real, 0.2 mole) of 30/, aqueous glyoxal, keeping the temperature at 15-22 C.
by cooling. Then the reaction mixture was heated at 80aC. for 1/2 hr. After cooling, 20 ml. of ether was added and the solution dried with KOH pellets. The ether was removed and the residue distilled under reduced pressure; b.p. 155-156 C./< 1 mm., nD25 1.5120, 67yo yield.
EXAMPLE 3
Glutaraldehyde (Bis(di - n - butylhydrazone) 25 To 41.2 g. (0.286 mole of 1,1-di-n-butylhydrazine was slowly added 57.2 g.
(14.3 g. real, 0.143 mole) of 25% aqueous glutaraldehyde, keeping the temperature at 15-20 C. by cooling. About 50 ml. of ether was added and the solution dried with KOH pellets. The ether was removed and the residue distilled under reduced pressure; b.p. 152-1530C./1 mm., nD'2 1.4732, 82/ yield. 30
