JPS58142922A - Modified rubber composition - Google Patents

Abstract

PURPOSE:A composition that is obtained by adding carbon black to a modified rubber resulting from reaction between rubber having unsaturated carbon bonds and an organic compound bearing carboxyl and aldehyde groups, thus showing high green strengt and good physical properties after vulcanization. CONSTITUTION:Carbon black is added to a modified rubber that is prepared by reaction between a rubber having unsaturated carbon bonds and an organic compound bearing carboxyl and aldehyde groups in the presence of a catalyst to give the objective rubber composition. When a homopolymer or copolymer of isoprene or piperylene is used, the reaction rate is high. As the organic compound, is used glyoxylic or formylacetic acid. As an acid catalyst, is used preferably SnCl4 or BCl3. The carbon black has preferably an average particle size of 10-50mmu and its amount is 1-200pts.wt., preferably 10-120pts.wt. per 100pts.wt. of the modified rubber.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention concerns a modified rubber composition having excellent green strength and physical properties after vulcanization.

Conventionally, in order to obtain rubber relatives with improved green strength and adhesiveness after vulcanization, rubbers into which polar groups such as carboxyl groups have been introduced, such as rubbers to which maleic anhydride or glyoxal have been added, have been used as rubbers. known to be used. However, these rubbers have drawbacks such as insufficient strength as a vulcanizate because side reactions such as gelation and molecular weight reduction of the rubber often occur during the modification reaction. -ru.

Therefore, as a result of various studies aimed at creating a modified rubber composition free from such drawbacks, the inventors of the present invention discovered that an organic compound having a carboxyl group and an aldehyde group in a rubber having an unsaturated carbon bond in the presence of an acid catalyst. The inventors have discovered that a composition prepared by blending carbon platter with a modified rubber obtained by reacting the same is extremely excellent in green strength, strong WL curvature and rebound properties of the vulcanizate, and has thus arrived at the present invention.

Rubbers having unsaturated carbon bonds (hereinafter sometimes referred to as unsaturated rubbers or rubbers) used for the preparation of the modified rubber in the present invention include butadiene, isoprene, piperylene, λ3-dimethylbutadiene, chloroprene, etc. Homopolymer rubbers of conjugated dienes, copolymer rubbers of two or more of these conjugated dienes, or copolymer rubbers of these conjugated dienes and other monomers, open polymer rubbers of cyclooleain such as cyclopentene and norbornene, etc. Typical rubbers having unsaturated carbon bonds include ring polymer rubbers, polymers of dienes such as ethylidene norbornene and cyclopentadiene, and polyolefin rubbers such as copolymers of dienes and olefins. Typical examples include natural rubber, guanyl rubber, polyisoprene rubber, polybutadiene rubber, styrene-butadiene copolymer rubber, butadiene-isoprene copolymer rubber, isoprene-styrene copolymer rubber, and butadiene-isoprene-styrene copolymer rubber. Polymer rubber, butadiene-piperylene copolymer rubber,
Butadiene loop Pyrene alternating copolymer rubber, polybentenamer ethylene-propylene/-diene copolymer rubber, butyl rubber, butadiene-acrylonitrile copolymer rubber, butadiene-isoprene/-acrylonitrile copolymer rubber, polychloroprene rubber, Styrene-butadiene
, styrene block copolymer rubber, styrene-isoprene-styrene block copolymer rubber, and the like. Among these, the reaction rate is generally high when isoprene homopolymer rubber or copolymer rubber, piperylene homopolymer rubber or copolymer rubber, and ethylene-propylene-ADY copolymer rubber are used.

In the present invention, organic compounds having a carboxyl group and an aldehyde group that are used include those having at least one of each group, including chain aliphatic compounds having up to 20 carbon atoms, a benzene ring, and a naphthalene ring. , compounds having aromatic rings such as pyridine rings and furan rings, and alicyclic compounds such as cyclopentane rings, cyclopentyl rings, and cyclohexane rings. In addition, these metal compounds can contain oxygen atoms, sulfur atoms, nitrogen atoms, and multiple pongee atoms as appropriate in the molecular chain.

Furthermore, as long as it does not adversely affect the reaction, any substituent such as a hydrogen atom, an alkyl group, an alkoxy group, an acyl group, a hydroxyl group, a nitrile group, or an adenyl group may be substituted in the molecule. can.

Furthermore, aliphatic metal compounds having carboxyl and aldehyde groups include glyoxylic acid, formyl acetate, 2-formyl acrylic acid, 6-formylhexanoic acid,
- Monoformyl octanoic acid, formylmethoxyacetic acid, ? −
Compounds having an aromatic ring such as phor(ruethyl acetic acid, 3-(carboxymethoxy)purvioaldehyde) include 1-, !- or 3-carboxybenzaldehyde, 8-
Formyl-6-acetyl-benzoic acid 1. j-11- or 3-formyl phenyl acetic acid 11.2-formyl phenyl acetic acid 1 m, 3-($1-formyl phenyl) propionic acid, 2-formyl cinnamic acid, L8-nataldehydic acid, 2 -13- or 4-formylphenoxyacetic acid, 2-formyl-4-methylphenoxyacetic acid,! −(
2-(2-)propio/II, 3-(2-
Formylphenoxy)propionic acid, 2-formyl-1
-Phenoxyisopallerianic acid, 5-(Z+, S- or 4-formylphenoxy) hexa/acid, (2-phor.

mylphenyl) methoxyacetic acid, 1 +, 2- or 3
-Formylphenylthio eml, 1-holdenru! -naphthyloxyacetic acid, [(5-form*-S-furyl)thio]acetic acid, (8-formyl-i-oxy:/-2) 1-1
-benzobilan-fuyloxy) vinegar 11.1-s
- or 3-carboxyphenoxyacetaldehyde, 2-(formethoxy)phenocyaacetic acid, etc., and alicyclic compounds such as 3-formylcyclopentanecarboxylic acid, 4-formylcyclopentenecarboxylic acid, Examples include 2-phorucitalohexanecarboxylic acid.

Among these metal compounds, those having a structure in which the carboxyl group and aldehyde group of the chemical compound can be easily approached sterically or thermodynamically within the molecule through an acid catalyst, and compounds having a 41IK aromatic ring. The reaction rate is high when a carboxyl group or an atomic group containing this group and an aldehyde or an atomic group containing this group are located at adjacent positions on the ring (or-4 position in a benzene ring). Therefore, it is the most preferable.

In addition, organic metal compounds having carboxyl groups and aldehyde groups are nonpolar or have a structure containing a large amount of relatively weakly polar hydrocarbon moieties, or those with a low one point are suitable for reaction operations because they have high solubility in hydrocarbon INK. It is.

The amount of the organic compound having a carboxyl group and an aldehyde group to be used is not particularly limited, but is usually 100% of the unsaturated rubber.
0.01 to 80 parts by weight, preferably 0.1 parts by weight
~S parts by weight.

The acid catalyst used in the preparation of the modified rubber in the present invention is selected from protic acids such as sulfuric acid, nitric acid, chlorosulfonic acid, p-toluenesulfonic acid and /1a hydrogen geyride, and commonly known Lewis acids. be done. Typical examples of Lewis acids are metal or metalloid halides,
For example, 81, B, mu1, gl, P, 8. 'r1,
V, )'@, za, Ga, Ga, As, 8e, Zr
, Nb.

Me, Cd, 8n, 8b, Ga, 'ra, W, HJ
Elements such as F, B1, U or PO18*0.80.8
Oxygen-element bonds such as O-1vo, halogenides or organic halides, or complexes thereof, which form a coordination metal with organic metal compounds having carboxyl groups and aldehyde groups. It's mt. Among them, it is particularly desirable that the color of the coordinating pongee body is orange (absorption wavelength 410 am) or more K111. More specifically, IIRl(
CHI) IBF, BO2, Mu JCj,, Mu INF,,
(He)m ICI,,POCj,,〒l Cj,,VC
l, , MOCl, , gacj4, (C%)8+sC4
,8bCj,,'f'@CJ,,TsBr4 and'we
d, etc. Korano5'chi8aCj1,B
CJ, WCj, BbC4, etc. are suitable because they have a high reaction rate and cause few side reactions such as gelation of rubber. Note that it is of course possible to use two or more types of protonic acids or Lewis acids, or to use a protonic acid and a Lewis acid in combination. The amount of the acid catalyst used is not particularly limited, but is usually 0.01-111 mol per mol of the organic metal compound having a carboxyl group and an aldehyde group.
Preferably it is o, oi to snow mole.

The reaction for preparing the modified rubber in Part 11 is usually carried out in the presence of a suitable solvent or in the absence of a solvent in a rubber kneading machine. Industrially, it is advantageous to carry out the reaction in rubber cement after detonation. When using a solvent, aromatic sm such as benzene and toluene,
Any solvent such as a buff-in solvent such as butane or hexane, or a halogenated hydrocarbon solvent such as dichloroethane or dichloroethane may be used; It is appropriate to make the situation more intense. Solvents that have a certain degree of solubility for organic metal compounds and acid catalysts containing carboxyl groups and aldehyde groups are particularly suitable from the viewpoint of HMIII, but are not necessarily limited to these. The organic compound having an aldehyde group and an aldehyde group may be added to the reaction system separately, or they may be mixed in advance (in this case, a chemical change may occur) and then added to the reaction system. In addition, the acid catalyst may be added in its entirety at the beginning of the reaction, or may be added in portions or continuously during the reaction. It is preferable to maintain the reaction system in an anhydrous state or under a limited amount of water in order to maintain the temperature and prevent reactions such as excessive gelation and cyclization of the rubber.Also, the presence of oxygen is usually undesirable. The reaction temperature is not limited to 411°C, but is usually -20°C.
The temperature range is from 0 to 200°C, preferably from 0 to 100°C.

The reaction time is also appropriately set from io seconds to sO time. When the reaction is carried out in a solvent, for example, by adding a large amount of alcohol or hot water, the reaction can be stopped and the rubber can be coagulated. Then, after removing the remaining catalyst by washing if necessary, the rubber is dried to obtain a modified rubber.

The type of carbon black to be blended into the modified rubber obtained in this way is not particularly limited, but carbon black with an average particle size of 10*Jg~SOOmfi f) is preferable, and its common abbreviations are EPC%MPC, HPC. .

CC, etc. Chi Il Black, 8AF, l8AF.

HAF% MAF, FEF, HMF, SRF, SPF.

Furnace black of GPF, MUPF, FF%CF轡,
It is appropriately selected from Samar black such as FT%MT, acetylene black, and the like. The amount of carbon platter used is usually 1 to 100 parts by weight of modified rubber depending on the application.
100 parts by weight, preferably 10'~! ! O parts by weight.

It can contain ordinary rubber compounding agents such as reinforcing agents and anti-aging agents other than carbon black.

Typical vulcanizing agents are sulfur and sulfur donors such as sulfur and thiazole, but other vulcanizing agents include peroxides, boriaones, metal oxides, urethane vulcanizing agents, and resin vulcanizing agents. It can be used as desired. In addition, vulcanization accelerators include sulfene, thiuram, thiazole, guanidine, mercaptotriazine, aldehyde-amine, etc., and vulcanization aids include carboxylic acids such as stearic acid and oleic acid, and stearic acid. Metalized metals such as zinc oxide, magnesium oxide, calcium hydroxide, and iron oxide are used as softening agents, and process oils such as paraffinic, naphthenic, and aromatic oils are used as adhesive agents. As an agent [is calcium carbonate]
Examples of reinforcing agents other than carbon black include silicic acid and its salts, and examples of antiaging agents include amines and phenols. The above-mentioned vulcanization accelerator and vulcanization aid are mainly used in the case of vulcanization using sulfur or a sulfur donor.

The modified rubber composition of the present invention may optionally include natural rubber, styrene-butadiene copolymer rubber, polybutadiene rubber,
Other rubbers, such as unmodified polyisoprene rubber, can also be included with optional openings.

The method of mixing the components constituting the composition of the present invention is not particularly limited, and various rubber mixing machines are usually used. They can also be mixed with rubber during the process to make carbon master patches and oil master patches, respectively.

The modified rubber composition of the present invention has excellent dynamic properties such as green strength in an unvulcanized state, tensile strength after vulcanization, fatigue resistance, and rebound resilience, so it can be used for passenger car tires, trucks, and buses. carcass, tread, sidewalls of large tires,
Suitable for use in bead fillers, inner liners, various anti-vibration rubbers, industrial belts, hoses, etc.

Next, the present invention will be specifically explained using examples.

The method for analyzing the modified rubber, the method for preparing unvulcanized blends and vulcanized products of the modified rubber, and the methods for testing their physical properties are as follows.

[Amount of organic compounds containing carboxyl groups and aldehyde groups (hereinafter sometimes referred to as organic compounds) introduced into rubber]

Quantification was carried out using gel perminication chromatography equipped with an ultraviolet absorption spectrophotometer, using the area of the aromatic ring of the organic compound added to the rubber molecule at a wavelength of 178 am IIc.

[Amount of carboxyl group introduced into rubber]

After purifying and removing the low-molecular components in the rubber, it was measured by neutralization titration.

[Preparation of rubber unvulcanized compound].

The modified rubber was heated and kneaded together with various compounding ingredients except for sulfur and vulcanization accelerator in the following compounding recipe in a small Banbury electric kimmer, and a small amount of sulfur and vulcanization accelerator was added to the obtained vortex metal.
A rubber unvulcanized compound was prepared by adding and kneading on a JL.

Delivery 46 times, A1゜81 season HAF carbon 50 aromatic oil 5 zinc oxide
5 Stearic acid 2 sulfur °2. s Oxydiethylene benzothiazyl sulfenamide O1 (vulcanization accelerator) Isopropyl-N&-phenyl-p-phenylenediamine 1.0 [Water C-less flexibility] 100 by Wallace Ravid Plastometer ℃
value at.

[Green strength] A 2-inch thick unvulcanized rubber sheet was made by compressing the unvulcanized rubber compound at IOOO℃ for 5 minutes, and a dumbbell-shaped JI No. 83 test piece was punched out and heated at 25℃ at see★/mjs.
The value of tensile stress at elongation WOO when a tensile test is performed at a tensile speed of z.

[Vulcanization speed]

14G” by oscillating disc rheometer
Time (Tes) until the torque measured at C reaches the maximum torque of 9SsK.

(Tensile test) The unvulcanized rubber arrangement was press-vulcanized at 145°C for a predetermined period of time to form a thick sheet, and a dumbbell-shaped No. 3 test piece specified in JIS-K @101 was punched out. cs o
It was carried out at a tensile speed of 0 proverb/ml.

〔Tensile strength〕

2. Punch out a short test piece with a width of 15 mm and a length of 106 mm from the vulcanized sheet F, and punch it at right angles to the side edge in the center of one side edge in the length direction with a sharp blade. The test was carried out at 25°C with a @- cut at a tensile speed of 100 cm/min. displayed.

[Repulsion modulus]

Measurements were made at 15°C using a Dunlop trypsometer.

Po134 soprene rubber (cis L4 knot 69896) 180
j1 was dissolved in 11 liters of dehydrated toluene K of 31, and heated at 15°C under a nitrogen atmosphere in a sealed glass container (separable flask).
While stirring, the organic metal compounds listed in Table 1 were added. Next, 11m on 11! The stated amount of 8aCJa was diluted with 40 times the volume of dehydrated benzene and gradually added dropwise, and the color of the solution was observed. After further stirring for the reaction time listed in Table 1, 500- methyl alcohol was poured in (it is presumed that this stopped the addition reaction). The obtained semi-solidified rubber S* was poured into 34 ml of methyl alcohol to completely solidify the rubber, and the solidified material was washed into small pieces. The coagulated strips were then immersed in 3 liters of methyl alcohol containing about 21i of an anti-aging agent (z6-di-tert-butyl-4-methylphenol), washed, and then vacuum dried - day and night. Therefore, the modified polyisoprene rubber samples shown in Table 1, B, C, and D.

I got E, F, and G.

Next, the physical properties of the unvulcanized and vulcanized materials of the samples shown in Table 1 were measured. The results are shown in Table 2.

From Table 8, samples B, C, and D of the present invention have particularly green strength,
It can be seen that the tensile strength and rebound modulus are excellent.

4゛Example 2 The same reaction as in Example 1 was carried out except that the organometallic compounds and acid catalysts used in Example 1 were replaced with those shown in Table 3, respectively, and the modifications shown in Table 4 were carried out. Polyisoprene rubber Eli) u, L J, K, L.

I got M.

Next, the above FFI sample was subjected to physical property tests in the same manner as in Example 1, and the results shown in Table 4 were obtained.

From the same table, it can be seen that all the coils are particularly excellent in green strength and tear strength.

Example 3 An experiment similar to that in Example 1 was conducted using the rubbers, organometallic compounds, and acid catalysts shown in Table 5 for the indicated times. 0. P was obtained.

-2, T', Next, physical property tests of each of the above samples and their corresponding unmodified rubbers were conducted in the same manner as in Example 1, and the results were 11116.
The results shown in the table were obtained. However, the formulation and vulcanization temperature were partially changed as shown below.

Sample N and corresponding unsweetened rubber: Zinc oxide S (parts by weight) Sulfur 111.5 Vulcanization accelerator 1
．． 1 Sample 0 and corresponding unmodified rubber: Zinc oxide 3 Sulfur 1.7 Vulcanization accelerator 1.4 Vulcanization temperature 160°C Sample P and corresponding unmodified rubber Heat Zinc oxide 1.14 Vulcanization acceleration - 1.8゛ vulcanization Vulcanization degree 1・O
℃ From the same table, it can be seen that the modified rubbers obtained according to the present invention have higher green strength, 5OO-tensile stress, tensile strength, and tear strength than the corresponding unfinished rubbers.

Example 4 The physical properties of a rubber composition prepared according to the formulation shown in Table 1 using the sample sample in Example 1 and unmodified polyisoprene rubber were conducted in the same manner as in Example 1. The results are shown in Table 7.

As is clear from No. y@, the same results as in Example 1 were obtained even if the amount of carbon black was varied.

Patent Applicant Nippon Zeon Co., Ltd. Proceedings Amendment Written March 23, 1980 Director General of the Patent Office 1, Indication of Case Patent Application @ 37 - :lS
't-1'l No. 2, Name of the invention (11) 3, Person making the amendment 4, Number of inventions to be increased by the amendment 05, Written amendment to the procedure to be amended (spontaneous) Chowa 58 5 May 13th, Japan Patent Office Director General Shun t Incident Indication No. 1157-25477 2, 尭＠O Name Modified Rubber Composition 5 To make an amendment 4 The increase in the number of cases due to the amendment 0 翫 Subject of the amendment - Detailed explanation of the invention in book 1 @ O column 4 Amendment O content
Corrected as silicic acid j in Dario.

(2) Oka IIs, page 1, line 0: ``2-Hor Kenru Ethyl Sukan is corrected to ``2-Hor Kenru Ethyl Sukan''.

(to) “1-.2-fork 5-” in the 5th Shinki line 5-4
Correct 0 (4) Okaki page 5 lines 5-6 gor1-, 2-matasha 3- to 2-, s- or 4-j.
Or correct it as 4-J - page 5, line 14, 0 "1-.
Correct “2-hor (ru 2)” to “fz-, s- or 4” (2) “1-hor (ru 2
Correct "-naphthyl-naphthyl-mongol" to r((1-hor(ru-2-naphthyl)o-life-shi)-acidj.

17) p1g4 Shinki line 1 “1-.2- or S-”
be corrected to "fz-, i- or 4-".

(2) - Correct page 4, line S, OrsJ to r2J.

-p! 2nd lumiru 2-naphthyluo medium)-1l1Jt
Corrected to ``Hol-Kenru-2 Naphthyl)odPV〕acetic acid.''
.

- Oka $1 I page 21 sho sample LO @ 0 rl - * Shibo Naka Sil Benzualde E de J t F! -Corrected as Clubenzaldehyde j in force J/1M. Copolymer rubber” is corrected.

- Add the following as 1(t) line 4 and below.
)tl) under reduced pressure (1 mmlf or less), 10 at SOC
Time drying, m water, Daitoyo, benzene 100-Wcs dissolved,
A small amount of unmoated area was removed and 90 polyisoprene rubber (syst)
4 Tsumugi membership fee 8 steamed rice) 140) was dissolved in IJO dehydrated Shibuta-hexane, and J.
) under a nitrogen atmosphere while stirring with ZSC, the above 0/
V first? Add the amount of liquid gold to TSF for 90 consecutive times.
t) Gradually add 8 mO14 dropwise as a benzene solution.
llEti yellowing), continued grinding for another 2 hours, 5
) Pour sdO methyl alcohol (this stops the addition reaction and is estimated to be 9) *lI6#E Rubber moat wave is poured into 5 volumes of acetone, and the rubber is completely coagulated. The coagulated material is washed into small pieces, and then about 2 tons
The coagulated strips were immersed in methyl alcohol S4 containing an anti-aging agent (λ6-Cimesial Petit-4-Methylphenol), washed, rolled, and then denatured by drying in a vacuum dryer overnight. Polyisoprene rubber sample Q
Obtained 90 purified round sample QO infrared absorption spectrum)
, 1704am-' (0-go) O absorbance! 14
40m+-'(O-a)()), the amount of carboxylic group O introduced is a0015 mol/100
) It was found that it was rubber, and the physical properties of the unvulcanized compound and vulcanized product were measured. The results are shown in Table S. Table 8

Claims (1)

[Claims] A modified rubber composition characterized in that carbon black is blended into a modified rubber obtained by reacting a rubber having unsaturated carbon bonds with an organic compound having a carboxyl group and an aldehyde group in the presence of an acid catalyst.