Rubber recycling technique by normal temperature and pressure...

1. 1
RV Rubber Reclaiming Agent (Devulcanizing Agent) Series
Technical Specifications of RV Rubber Reclaiming Agent (Sheet Master Batch):
Note: * not mandatory
Technical Specifications of RVS Rubber Reclaiming Agent (Powder)
(Code of RV rubber reclaiming agent powder supply form：RVS)
white or light yellow
≤8%
≤28%
low
soluble in acetone, benzene, carbon tetrachloride and naphtha with medium solubility
Appearance:
Color:
Specific weight:
Mooney viscosity
ML1+4, 100℃: 50±10*
Odor: low
Solubility: soluble in acetone, benzene, carbon tetrachloride and naphtha with medium solubility
thick sheet
white or light yellow
1.3 ± 0.10
Appearance: powder
Color:
Heating Loss:
Burning Residual:
Odor:
Solubility:
Application：
It can make the waste vulcanized rubber or scorching rubber revived under normal temperature and pressure in short time.
Principle：
RV revived rubber technique is, through mechanical shearing,to
make RV rubber reclaiming agent wrapped evenly on the surface
of the waste rubber powder particles and infiltrate into the rubber
powder particles by the wetting effect so as to reduce the bond
energy of S-S cross-linking bond, untie the S-S cross-linking
bond effectively within a short time without destroying S-C bond
and C-C bond, thus make waste rubber restore its activity.
The rubber revived by RV rubber reclaiming agent can vulcanize
without any vulcanizing agent and accelerator. This kind of
rubber is named as RVR revived rubber, (it is revived to the final
rubber compound, which is completely different from common
reclaimed rubber), it restores the basic property of the raw rubber,
and if it is calculated in tensile strength, it can be restored to
50-85% of the raw rubber. Using RVR alone to revive rubber
products or to substitute 10-70% of the raw compound rubber can
reduce costs, guarantee the quality and increase the efficiency.
Reviving the scorching rubber by using less RV rubber reclaiming
agent gets better effect.
RV revived rubber technique is exquisite, simple and non-toxic,
with low energy consumption and without hard labor intensity,
which can be finished under normal pressure and temperature.

2. Application Scope and Variety:
Application Scope :RV rubber reclaiming agent is applicable to all kinds of rubber vulcanized by sulfur or metallic oxide/sulfur.
RV - NR/BR/SBR applicable to NR, SBR, BR and their blends.
RV - EPDM applicable to EPDM
RV-NBR applicable to NBR
RV-CR applicable to CR
RV-IIR applicable to IIR
RV-MDIR applicable to Medical rubber products
RVS - NR/BR/SBR applicable to NR, SBR, BR and their blends.
RVS - EPDM applicable to EPDM
RVS-NBR applicable to NBR
RVS-CR applicable to CR
RVS-IIR applicable to IIR
RVS-MDIR applicable to Medical rubber products
The above-mentioned products are provided in the form of sheet master batch, and are convenient to use on the open mill as well as on
the refining mill.
The above-mentioned products are provided in the form of powder materials, and are convenient to use on the open mill, the refining mill
and the internal mixer with an automatic folding auxiliary machine.
Note: when reviving the waste rubber produced by mixing several kinds of rubber, use the rubber reclaiming agent with higher content of
waste rubber. e.g., the waste rubber produced with a mixture of 20% NR + 80% EPDM, and RV-EPDM is adopted as reclaiming agent.
RV rubber reclaiming agent has passed the inspection of RoHS and PAHs.
Applicable Recipe: (the ratio shown on the recipe is weight ratio)
A.Simple recipe: (suitable for the users to inspect the effect of the reclaiming agent, low-cost application and revive the scorching rubber)
Waste rubber 100
RV rubber reclaiming agent 3( According to the scorching degree for the scorching rubber 0.5-2)
Processing aid * 2(Reduce the viscosity of the rubber compound and increase the plasticity)
Raw compound rubber or plasticated rubber 5-10(Convenient to make blend evenly and sheet with high efficiency, quick
sheeting and power saving)
Total 110-115
Waste rubber 100
RV rubber reclaiming agent 3( According to the scorching degree for the scorching rubber 0.5-2)
Total 103
B. Recommended recipe: ( Suitable for the rubber products factories to use the waste trimmings from our factory)

3. 3
C. Standard recipe: (suitable for applicable recipe in producing RVR revived rubber)
Waste rubber 100
RV rubber reclaiming agent 3( According to the scorching degree for the scorching rubber 0.5-2)
Processing aid * 2(Reduce the viscosity of the rubber compound and increase the plasticity)
plasticated rubber 3-6(Convenient to make blend evenly and sheet with high efficiency, quick
sheeting and power saving ,to reduce Mooney viscosity)
Total 108-111
(*The statement of the processing aid is as the same as the above .)
RVR Revived Rubber is directly revived to final rubber
compound, and can vulcanize directly without adding any
accelerator or vulcanizing agent. Compared wtih common
reclaimed rubber, it can save about 500-800 yuan/ton of additives
when producing finished products.
Using the RVR Revived Rubber alone can produce relatively
low-grade products. It is recommended to mix the RVR Revived
Rubber with the raw compound rubber, and the highest mixing
rate can be 90%, to be adjusted by you accordingly. Method of
mixing with raw compound rubber: first, add RVR to the open
mill, mixing and mill running, then add the raw compound rubber,
mixing evenly and sheeting, and then have molding and
vulcanizing. If the vulcanizing speed is too fast in the process,
reduce the dosage of the accelerator and sulfur in the raw
compound rubber.
RVR Revived Rubber produced by RV rubber reclaiming agent
has the following characteristics:
It is with high anti-recovery, low permanent deformation and
compression, high rebound elasticity and low rolling resistance.
Shortening the mix time can reduce the temperature of mixing,
calendering and extrusion; improve the tackiness of the
semi-finished products and the intensity of the rubber compound,
and reduce the extrusion expansion and contraction.
Storage life: RV should be kept in cool and dry places for 3 years,
and RVS should be kept in cool and dry places for 1 year.
Package: 25kg/bag (woven bags lined with bag films)
Brief Introduction of RV Revived Processing Technique:
(*The processing aid can be substituted by 0.5-2 parts by weight
of stearic acid, or 3-12 parts by weight of process oil, or
tackifying resin. The softening point of the tackifying resin shall
be 80±20�, and will not become hard while vulcanizing. These
requests are to insure the good sheeting effect while milling to
make the RV rubber reclaiming agent better mix with rubber
powder. Users should decide whether add the processing aid or
not according to the condition of the waste rubber. RW-EPA
rubber homogenizing agent produced by our company can be
co-used. 10 parts by weight of the processing aid and raw
compound rubber or 5 parts by weight of plasticated rubber must
be added 8-10 min after the reaction of the waste rubber and the
RV rubber reclaiming agent.)
First，adjust the roll pitch of the open mill to the minimum(zero
pitch), put 100 parts by weight (10-40 meshes) of rubber powder
or waste rubber leftovers and 3 parts by weight of RV rubber
reclaiming agent to the open mill, and mill for 10 min so that they
can be evenly blended; then adjust the roll pitch to 0.5 mm, add
the processing aid and compound rubber for 5 min mixing before
sheeting. The roll temperature of the open mill should be below
70℃.
It is recommended to use the refining mill, which has good effect
and high efficiency; the whole process can be finished only in 10
min. Using RV technique automatic folding machine can reduce
the labor intensity with more even mixing. This equipment can be
customized by our company.
The Application Methods and Features of RVR Revived Rubber
(1) RV rubber reviving technique is one way of rubber recycling
by cutting S-S bond without influencing S-C bond and C-C bond.
(2) RV rubber reclaiming agent is safe, color stay, non-pollution,
non-blooming and has passed the inspection of RoHS and PAHs.
(3) The processing time is short, and the work can be finished on
the open mill in only 10-15 min. (Different kinds of waste rubber
have quite different time differences.)
(4) RV rubber reviving technique can be completed with the
Advantages of RV Rubber Reclaiming Agent:

4. 4
RV Rubber Reclaiming Agent Second Generation RV2
——RMCD Rubber Mechanochemical Chain Scission Depolymerizing Agent
existing equipment of the factory.
(5) All kinds of rubber waste, including the NR and SR or
blending of NR and SR can be recycled.
(6) It is effective to both mature rubber and semi-mature rubber
compound.
(7) It can keep the color of the rubber compound suitable for the
reviving of the light color products.
(8) It can vulcanize without adding any sulfur or accelerator and
can save cost.
(9) The wear resistance as well as ageing property of the rubber
compound recycled by the RV rubber reviving technique is better
than that of any other reclaimed materials (such as common
reclaimed rubber, rubber powder and activated WRP, etc.).
(10) The process is completely without any air pollution and
water pollution, and is in accordance with environmental
protection requirement.
(11) The RV revived rubber products made by the RV rubber
reviving technique are completely odorless, tasteless and are
widely used with high value.
(12) RVS products make the use of the rubber powder expending;
they can be used in the production of desulfurizing rubber powder
at normal temperature and can also be used in modified asphalt
rubber (CRMA)as well as rubber modified plastics, etc.
For details of the RV technique, please refer to the Rubber
Recycling System-Basic Introduction and Application Handbook
of RV Technique
After years of concentrate study, we finally broke the technical
bottleneck and successfully developed the second-generation RV
rubber reclaiming agent- RMCD rubber mechanochemical chain
scission depolymerizing agent (hereinafter referred to as RV2
generation). It overcomes the disadvantages of domestic and
foreign relevant products, which have slow sheeting, high
Mooney viscosity, high energy consumption, etc. and surpasses
the first generation product RV rubber reclaiming agent of our
company and the De-link of Malaysian.
Characteristics: Applied by many domestic manufacturers, it
obviously shortened the processing time, increased the break
elongation, and reduced the Mooney viscosity of the revived
rubber. What is the most important is that the dosage is induced. It
needs only 2 parts by weight of RMCD (RV2 generation) per 100
parts by weight of waste rubber, which saves the company
reclaiming agent cost of 200 yuan more than the first generation
when recycling one tone waste rubber, and realizes energy saving
and emission reduction.
The revived rubber can vulcanize without adding any vulcanizing
agent and accelerator, which can save the processing aid valued
500 yuan, (GB/T13460-2008 the standard recipe of the reclaimed
rubber is: reclaimed rubber 300g,accelerator NS 2.4g,zinc oxide
7.5g, sulfur 3.5g, stearic acid 1.0g；of which one ton of the
reclaimed rubber need to consume the processing aid valued 500
yuan to vulcanize production)，so one ton of the waste rubber only
needs the reclaiming agent valued 200 yuan to revive to the
rubber product.
If 20% of the revived rubber is used to substitute the raw
compound rubber, the dosage of the accelerator in the raw
compound rubber can be reduced about 20%, which can further
save the costs about 100 yuan. At present, RMCD rubber
mechanochemical chain scission depolymerizing agent
(hereinafter referred to as RV2 generation) is suitable for the
application of deep products.

5. 5
Technique: First, turn the roll pitch of the open mill to the
minimum (zero pitch, add the rubber (10-40 meshes) or 100 parts
by weight of the waste rubber leftovers and 2 parts by weight of
the rubber reclaiming agent RV2 Generation to the open mill, mill
for 12 min and mix evenly; then sheet out. The roll temperature
should be below 70℃.
Using the refining mill has good effect and high efficiency, and
the whole process can be finished in 8 min.
At the same time, we developed the coordination reclaiming of
the rubber mechano-chemical reclaiming reactor and the rubber
double-screw extruder, which realized the successive production.
We realized the reviving of the waste rubber at normal
temperature and pressure, and formed the assembly production
line, which is a leap of the rubber reviving technique.
Principle：a subject that when the solid material is added with
mechanical energy, its solid state, crystal structure, etc. change, as
a result that the physical and chemical property change is called
mechano-chemical. The rubber machinery sheering and
shattering process is accompanied with the impact of the
mechano-mechanical, when the force works on the waste rubber,
the force initiation is produced, and the active particles are
generated, at the same time creating force splitting, and generating
molecule chain break sheet with big free radicals property①.
When degrading the vulcanized rubber, the free radicals are on the
C—C= bond instead of C—S bond, but when there is C—Sn—C
bond, 30% C—C bond will be directly destroyed, while 70% is
chain broken caused by the shift of the unpaired electron to the
sulfur created by breaking the C—C bond②. The splitting does not
always happen on the weakest bond, but can also happen on the
stronger bond, when there is weaker C—S bond, it can split on the
C—C bond③. As the atomic energy of the RMCD rubber
mechano-chemical chain scission depolymerizing agent and the
lone pair electrons of the sulfur atoms among the sulfur organic
compound form a coordination bond, making S—S bond and S—C
bond be weaker, and cutting S—S bond and S—C bond under the
mechanical force and in this way we can reclaim the waste tire
rubber powder. As the rubber mechano-chemical chain scission
depolymerizing agent RMCD has many chain-break options, the
break of the rubber molecule main chain C—C bond is small, so
the revived rubber keeps higher physical property.
References: ①②③H.K. БАРАМБОйМ High Molecular
Compound Mechano-mechanical