Ozone erosion of rubber often occurs on the surface.
The ozone concentration in the air around us is increasing year by year.
Ozone must respond to the application.
The result of the erosion of rubber products is cracks, which will eventually lead to the complete failure of rubber products.
1
Waxy anti-ozone agent
In order to improve the ozone resistance of rubber mixture under static conditions,
Usually it is a mixture of various waxes.
Such as low molecular weight paraffin,
macromolecule
* * * The amount of mixture (such as paraffin wax or microcrystalline wax) is limited to improving the static ozone resistance of rubber compounds. If you add too much,
In fact, it will reduce the dynamic ozone resistance of compounds.
2
ursol
Standard pure protein derivative
antiozonant
Ursol
Standard pure protein derivative
It is an effective anti-ozone agent, which can give the compound good ozone resistance even under dynamic conditions.
Many times will also be selected.
6PPDs
As an effective anti-ozone agent under dynamic conditions.
will
6PPD
(long-term) and
77PPD
(short-term effective) can comprehensively improve the ozone resistance of rubber compound.
three
microencapsulation
Programming instruction
correct
6PPD
The implementation of microcapsule technology can be considered,
Cellulose acetate can be selected as the microcapsule.
To encapsulate in microcapsules.
6PPD
Adding it to the rubber compound can not only protect the rubber compound from ozone erosion for a long time, but also prevent ozone erosion.
6PPD
Move out.
four
. wax
/PPDs
In order to make the compound have good ozone resistance under static and dynamic conditions,
Then choose a wax and use p-phenylenediamine.
Class, such as
6PPD
Antiozonant.
five
.
National broadcasting corporation
antiozonant
Nickel dibutyldithiocarbamate
(NBC)
about
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
、
China Railway (China Railway)
and
Small tentacles (same as small bristles)
Generally speaking, it is a good electrostatic anti-ozone agent, but it does not
Rubber compounds suitable for use under dynamic conditions.
six
Molecular Weight and Solubility of Antiozonants
An effective antiozonant must be compatible with the rubber mixture,
And must be able to migrate to the surface to play the role of ozone erosion.
through
Usually its migration speed depends on its molecular weight.
}
Dissolve in
7.6QDI
Sulfur vulcanized diene rubber compound should be selected.
N-
phenyl group
Tong -EN
- 1
3-=
Methyl butyl p-quinoline imine
(once every six years)
Do anti-ozone
Agent, because after vulcanization, it will chemically combine with rubber main chain or carbon black to improve the ozone resistance of rubber compound. because
Well,
According to reports,
In some cases,
6QDI
compare
6PPD/TMQ
It has good antioxidant effect.
There are also reports that,
6QDI
Convert parts into
6PPD
And plays a role in resisting ozone erosion.
8.77PD
77PD
(alkyl)
Programming instruction
) is mainly used for electrostatic ozone protection.
U
And it is short-term protection. Under dynamic conditions, usually
Not used alone, usually with alkyl, aryl
Programming instruction
The compound has good odor resistance under static and dynamic conditions.
Oxygen. usually
6PPD
and
77PD
Will press
2: 1
Proportion (mass ratio) is used together, the former is used for ozone protection under dynamic conditions,
The latter is ozone protection under static conditions.
nine
.
TMQ/6PPD
if
TMQ
If it is not enough in ozone resistance or fatigue resistance, it can be used together.
6PPD[ N-
phenyl group
Tong -EN
'
-
(
1
3-
two
Methyl butyl)
-
Ursol
]
. This is especially true for rubber compounds exposed to oxygen and ozone.
Important. Therefore,
TMQ
and
6PPD
It is very common to use them together.
I
10
Non-colored acetal anti-ozone agent
For white or colored compounds,
Non-pigment antioxidants can be used.
Cyclic acetal antioxidants can be considered.
(
Bayer
public
separate
Vulkazon AFS
) as an anti-ozone agent for various rubber compounds.
It is reported that compared with p-phenylenediamine antioxidant, bis (p-phenylenediamine)
-
(
1
2
three
6-
Tetrahydrobenzaldehyde)
-
Pentaerythritol acetal can be given
China Railway (China Railway)
、
Butyl rubber (abbreviation of Isobutylene-Isoprene Rubber)
、
CIIR
、
BIIR
Compounds with the same size have higher ozone resistance.
1 1
Butyl rubber and halogenated butyl rubber
Butyl rubber and halogenated butyl rubber have good ozone resistance.
Low unsaturation
[
such as
o
.
8%
(molar concentration)
]
Butyl rubber has better ozone resistance because of its low degree of unsaturation.
Ozone erosion is less likely.
12
DNPD/Zn0
sclerosis
BIIR
Combined use of zinc oxide
ordinary
ordinary
-
two
-B.
–
Naphthyl p-phenylenediamine
(DNPD)
or
Goodrich
The company's products
Ai Jie Li te Bai
Vulcanized butyl bromide rubber can give rubber better ozone resistance.
13
.
Business information management system
Brominated isobutylene
-
P-methylstyrene rubber
(BIMS)
Has better ozone resistance than some butyl rubber or halogenated butyl rubber,
because
Business information management system
It's completely saturated.
in a
NR
In ternary tire sidewall compound with matrix,
use
Business information management system
Instead of partially halogenated butyl rubber or
EPDM
can
So as to obviously improve ozone resistance and fatigue crack propagation resistance.
14
Dioxime vulcanization of butyl rubber
Butyl rubber compound is vulcanized by dioxime, which can improve the ozone resistance of rubber compound.
15
Vulcanization of halogenated butyl rubber by alkylphenol disulfide
When halogenated butyl rubber is mixed with other unsaturated elastomers,
Selecte alkylphenol disulfide for vulcanization,
Could be important.
land
Improved glue
Ozone resistance of materials.
16
.
EPDM
and
Enterprise project management
Both EPDM and EPDM have good ozone resistance.
17
... high gloss and ozone resistance.
In order to make the surface of rubber products have high gloss,
A mixture of amphiphiles with a highly saturated backbone should be selected.
* * * mixture
Containing these saturated components,
It has good ozone resistance and does not need to add anti-ozone agent.
If an anti-ozone agent is used,
will
appear
"icing"
Phenomenon,
Migration to the surface will affect the luster of the product.
The saturated main chain elastomer comprises
EPDM
、
BIIR
、
CIIR
and
Business information management system
Wait a minute.
18.
Avoid using
NR
If a strong anti-ozone agent is not used,
Natural rubber has poor ozone resistance,
So it is generally used.
NR
Along with other anti-ozone bombs
A mixture of sexual bodies.
19.NR
Covering glue
An all-natural rubber engine bracket installed on the engine,
Its surface is provided with two layers of covering glue,
Wherein the bottom layer is matched according to a certain proportion.
Bonded and crosslinked chloroprene and octene polymers,
The upper layer is crosslinked halogenated butyl rubber/octene polymer.
exist
Two layers of covering glue on the surface of the rubber bracket,
Can effectively resist the erosion of natural rubber by ozone and thermal oxidation,
This is mainly
Because it reduces the main chain breakage caused by the diffusion of ozone and oxygen into natural rubber.
The fatigue test results show that,
There are two floors here.
The fatigue life of rubber engine bracket is obviously improved after rubber coating.
20.NR/EPDM
* * * mixture
Sulfur and peroxide are vulcanized together.
NR/EPDM
***
1
Among the Kun objects,
EPDM
This will make the compound have better ozone resistance.
about
NR/EPDM
* * * mixture,
rise
EPDM
This dose will improve the ozone resistance of * * * compounds.
Theoretically,
EPDM
The optimum dosage of is
35% - 40%
(Mass fraction)
(
EPDM
Become a continuation of the Tao)
. Because with
EPDM
The increase in dose,
* * * Vulcanization may be a problem,
And will lead to performance degradation.
The study found that,
External force relay (abbreviation of external power relay)
exist
NR
The dispersed micro-regions in the matrix will be reduced.
Rubber mixture ozone turtle crack,
External force relay (abbreviation of external power relay)
exist
NR
The optimum dosage of is
35%
- 45%
(Mass fraction)
Can effectively improve
Ozone resistance of rubber mixture.
2 1
NR/CIIR
* * * mixture
exist
NR/CIIR
* * * In the mixture,
CIIR
The ratio can be higher, which is the same as
NR
More compatible than
EPDM
and
NR
Stage of
Capacitance is better.
but
EPDN
Equivalent to adding an anti-ozone agent.
NR
Yes,
So sometimes it is necessary to mix the three.
To rubber mixtures with good physical properties and ozone resistance.
22
.
China Railway (China Railway)
It is reported that the ozone resistance of chloroprene rubber can reach
50pphm
(50 X 10 -8)
, join
1-2
Two copies (by mass)
Aryl p-phenylenediamine antiozonant can make
China Railway (China Railway)
The ozone resistance of rubber compound is improved to
100pphm
However, this antioxidant will shorten.
The scorch safety period of rubber compound should be matched with vulcanizing agent.
23
.
CR/EPDM
alloy
exist
Neoprene/EPDM =
70/30
(mass ratio) * * * Mixing, adding
10
Number of copies (by mass)
Escol
Compatibilization of Acidic Terpolymer
Reagent (ethylene-methacrylate)
-
Acrylate terpolymer)
Resistance of this compound to notch growth of Demecia (flex)
Good heat resistance and ozone resistance. This is a very recommended formula for transmission belt rubber.
24
, can mix wisdom.
polyurethane
and
Small tentacles (same as small bristles)
* * * mixture
exist
Small tentacles (same as small bristles)
In the rubber mixture, gradually add the miscible
polyurethane
Can effectively improve the ozone resistance of the rubber compound.
25
. Epichlorohydrin rubber
Epichlorohydrin rubber itself has good ozone resistance.
26
silicon rubber
Silicone rubber is an elastomer with good ozone resistance.
27
polyacrylate rubber
Polyacrylate rubber is an elastomer with good ozone resistance.
28
centimetre
Chlorinated polyethylene elastomer is a kind of elastomer with good ozone resistance.
29. Command and Service Module
Chlorosulfonated polyethylene rubber itself has good ozone resistance.
30
Polyurethane elastomer
Compared with ordinary diene rubber, polyurethane elastomer has the outstanding advantage of good ozone resistance.
3 1.HNBR
HNBR
It can still be vulcanized with sulfur clips because it still has some unsaturated bonds.
If the oxide is vulcanized, it will increase.
Its ozone resistance.
32
.
NBR/PVC
* * * mixture
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
and
polyvinyl chloride
* * * After mixing,
Its ozone resistance will be significantly improved.
will
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
Pure glue and plasticization
polyvinyl chloride
In the mixer
Granulating after melting and mixing, which is convenient for later mixing and matching. It was found that emulsion polymerization
polyvinyl chloride
(used as plastic.
Sol) is most suitable for
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
* * * Mixing can make the compound have better ozone resistance and stress-strain performance. exist
NBR/PVC
* * * In the mixture, add
polyvinyl chloride
This dosage can improve the ozone protection performance of the compound.
33
.
NBR/EPDM
* * * mixture
Good oil resistance
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
Stick if and.
30
Number of copies (by mass)
EPDM
***; Mixing can improve its ozone resistance, but it will
Reduce oil resistance. however
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
and
EPDM
The compatibility of is poor, if not very good.
1
Mix and vulcanize the mixture.
The performance will be poor, so we should pay attention to the selection of suitable curing system and the compatibility of the two. For example,
wood
and
society
study
It is found that dithiocarbamate has long chain alkyl and can be used in vulcanization system. Besides,
Bergstrom
study
Found that,
o
2
Part (testis) sulfur,
o
.
five
Number of copies (by mass)
Columbia Broadcasting System (CBS)
and
2.5
Number of copies (by mass)
40% DCP
Parent mixture
It is used for
NBR/EPDM
Good curing system.
Mitchell
The study found that,
will
EPDM
Firstly, mixing with carbon black to obtain master rubber,
Reconnect with ...
Nitrile-butadiene rubber (abbreviation of nitrile-butadiene rubber)
Mixing can improve compatibility and other properties.
34
, talcum powder
It is found that talcum powder can give the compound some ozone resistance.
35
. white carbon black
In the inclusion
EPDM
Adding silica into the sidewall rubber filled with carbon black can effectively improve the ozone resistance of the rubber compound.
Tear resistance and crack growth resistance.