NATURAL NATURAL RUBBERRUBBER
Gift of natureGift of nature
Significant influence on the Significant influence on the quality of human lifequality of human life
A green commodityA green commodity
A relatively short historyA relatively short history
Provides livelihood to over 10 Provides livelihood to over 10 million small farmersmillion small farmers
NATURAL NATURAL RUBBERRUBBER
Major source-Major source-Hevea brasiliensisHevea brasiliensis
Total global production (2004) - 8.24 Total global production (2004) - 8.24
million tonnesmillion tonnes
Total consumption (2004) - 8.11 Total consumption (2004) - 8.11
million tonnesmillion tonnes
Production in over 20 countriesProduction in over 20 countries
SALIENT FEATURES
Major producing Major producing
countries : countries :
Thailand,Indonesia Thailand,Indonesia
Malaysia,India,China, Malaysia,India,China,
VietnamVietnam
Major consuming Major consuming
countries : countries :
China,USA,Japan, China,USA,Japan,
India,Malaysia,KoreaIndia,Malaysia,Korea
Special characteristics of NRSpecial characteristics of NR High strengthHigh strength Low heat generationLow heat generation High tack and green strengthHigh tack and green strength Excellent processabilityExcellent processability Excellent resistance to chipping, chunking and tearExcellent resistance to chipping, chunking and tear EconomyEconomy
Relatively inferior resistance to ageing, weathering and Relatively inferior resistance to ageing, weathering and heatheat
Swells in contact with petroleum oilsSwells in contact with petroleum oils High air permeabilityHigh air permeability Relatively inferior traction and wet skid resistanceRelatively inferior traction and wet skid resistance
RUBBER PLANTATIONRUBBER PLANTATION
Ribbed sheet rubberRibbed sheet rubber Concentrated latexConcentrated latex Block rubber Block rubber Crepe rubberCrepe rubber
CROP (RUBBER)CROP (RUBBER)
LatexLatex Field coagulumField coagulum
80 %80 %
Marketable forms of raw rubberMarketable forms of raw rubber
20 %20 %
Typewise production of NR in India (2002-03)Typewise production of NR in India (2002-03)
TypeType Quantity (MT)Quantity (MT) % Share% Share
RSSRSS 450215450215 69.369.3
Latex concentrate (DRC)Latex concentrate (DRC) 7432574325 11.511.5
Solid block rubberSolid block rubber 7494074940 11.511.5
Pale Latex Crepe Pale Latex Crepe 17501750
OthersOthers 4820548205 7.77.7
TotalTotal 649435649435
NATURAL RUBBERNATURAL RUBBER
INDUSTRIAL RAW MATERIAL FROM NATURE
SYNTHESISED BY THE TREE
UNDEGRADED TILL IT COME IN CONTACT WITH AIR
CIS-POLY-ISOPRENE
NATURAL RUBBER – NATURAL RUBBER – MARKETABLE FORMSMARKETABLE FORMS
SHEET RUBBER (RSS)
CREPE RUBBER
TECHNICALLY SPECIFIED RUBBER (TSR)
LATEX CONCENTRATES
NATURAL RUBBER – SHEET NATURAL RUBBER – SHEET RUBBERRUBBER
LOWER PROCESSING COST
SIMPLE MACHINERY
ADOPTED BY SMALL GROWER SECTOR
STEPS INVOLVED IN SHEET RUBBER PROCESSING
Sieving
Bulking
Dilution
Coagulation
Sheeting
Drying
Grading
RSS IX Colour
RSS 1 Extent of dryness
RSS 2 Mould growth
RSS 3 Tackiness
RSS 4 Blisters
RSS 5 Dirt
Ribbed Smoked Sheet Ribbed Smoked Sheet GradesGrades
CREPE RUBBERSCREPE RUBBERS
Field coagulum crepe
Pale latex crepe
PALE LATEX CREPEPALE LATEX CREPE
Removal of pigments
Fractional coagulation
Bleaching
PALE LATEX CREPE - PALE LATEX CREPE - DefectsDefects
Fungal spots – Brown discolouration
Grey or dark colour
White spots and streaks
Tackiness
Poor lamination strength
PALE LATEX CREPE -PALE LATEX CREPE -ApplicationsApplications
Pharmaceutical products
Light coloured and transparent goods
Adhesives
Tapes
Tubings
Derivatives such as chlorinated rubber
TECHNICALLY SPECIFIED TECHNICALLY SPECIFIED RUBBERRUBBER
LATEX GRADES
FIELD COAGULUM GRADES
TECHNICALLY SPECIFIED TECHNICALLY SPECIFIED RUBBERRUBBER
SPECIFICATION PARAMETERS
DIRT
VOLATILE MATTER
PLASTICITY
PLASTICITY RETENTION INDEX (PRI)
NITROGEN CONTENT
ASH CONTNET
Soaking
Initial size reduction Pre-breaker
Blending
Creping
Final size reduction Hammer mill
Drying
Pressing Testing and Grading
Packing
TSR PRODUCTION – FC GRADESTSR PRODUCTION – FC GRADES
TECHNICALLY SPECIFIED RUBBER - TECHNICALLY SPECIFIED RUBBER - ADVANTAGESADVANTAGES
The consumer has the choice
More consistent
Impurities can be assessed
Being marketed in compact polyethylene wrapped bales, contamination on storage handling and transportation is minimum.
Minimum storage space
Reduction in processing time
TECHNICALLY SPECIFIED RUBBERTECHNICALLY SPECIFIED RUBBERISNR 3CVISNR 3CV Tyres, Engineering Tyres, Engineering
components, extruded and components, extruded and calendared productscalendared products
ISNR 3LISNR 3L Light coloured pharmaceutical Light coloured pharmaceutical feeding bottle teats, Industrial feeding bottle teats, Industrial rollers for paper and printing rollers for paper and printing industry industry
ISNR 5ISNR 5 Conveyor belts, cycle tubes, Conveyor belts, cycle tubes, engine mountings, footwearengine mountings, footwear
ISNR 10, ISNR 10, 2020
TyreTyre
ISNR 50ISNR 50 Handmade hose, footwear, Handmade hose, footwear, mats, moulded hosemats, moulded hose
NR Quality Issues
Consistency
Contamination
Undried rubber
Packaging
NR Quality Issues – Consistency
NR is subject to inherent variability
Variation in plasticity to be minimum
NR Quality Issues – Contamination
Rubber gets contaminated during tapping, collection, processing and packaging
The contaminants do not disperse during compounding.
NR Quality Issues – Undried rubber
Undried rubber prevents effective dispersion of ingredients during compounding
Cause blisters
Only 13% of total NR production Only 13% of total NR production
Mainly from field coagulumMainly from field coagulum
Proper attention is not given to the collection Proper attention is not given to the collection
and storage of the raw materialand storage of the raw material
TSR production in IndiaTSR production in India
The storage of the field The storage of the field coagulumcoagulum
Often stored in the wet conditionsOften stored in the wet conditions Contaminated with sand and bark Contaminated with sand and bark
particles and other foreign matterparticles and other foreign matter Polythene and jute sack fragments, Polythene and jute sack fragments,
plastic cord/ metallic stringsplastic cord/ metallic strings
Inferior raw material results inInferior raw material results in
Lower quality of TSRLower quality of TSR
Non-uniformity and inconsistency in quality Non-uniformity and inconsistency in quality
Lower resistance to thermo-oxidative degradationLower resistance to thermo-oxidative degradation
The oxidizability of raw rubber has an important The oxidizability of raw rubber has an important bearing on the processing behaviour and bearing on the processing behaviour and vulcanizate performancevulcanizate performance
The plasticity retention index (PRI) test gives a The plasticity retention index (PRI) test gives a rapid assessment of the resistance of raw NR to rapid assessment of the resistance of raw NR to thermo-oxidative degradationthermo-oxidative degradation
OBSERVATIONS…OBSERVATIONS…
PPo o of autocoagulated rubber increases on storageof autocoagulated rubber increases on storage
The PRI of autocoagulated rubbers are lower than the The PRI of autocoagulated rubbers are lower than the acid coagulated rubbersacid coagulated rubbers
PRI falls as the length of time from coagulation and PRI falls as the length of time from coagulation and processing is increasedprocessing is increased
In many cases due to low PRI the rubber may fail to In many cases due to low PRI the rubber may fail to meet the requirements specified for a particular grade. meet the requirements specified for a particular grade. Hence it is very essential to preserve PHence it is very essential to preserve Poo & PRI of the raw & PRI of the raw material.material.
OBSERVATIONS…OBSERVATIONS…
One major reason for the low PRI of field coagulum during storage is the bacterial decomposition of proteins and other non rubber constituents in the rubber.
Copper in fresh latex might complex with Copper in fresh latex might complex with proteins and amino acids and in this form it does proteins and amino acids and in this form it does not impart any adverse effect on the ageing of not impart any adverse effect on the ageing of NR. NR.
When the latex is exposed to microbial activity When the latex is exposed to microbial activity the microbes degrade the complex and release the microbes degrade the complex and release free copper which is reported to be a powerful free copper which is reported to be a powerful pro-oxidant. pro-oxidant.
One major reason for the low PRI of field coagulum during storage is the bacterial decomposition of proteins and other non rubber constituents in the rubber.
Copper in fresh latex might complex with Copper in fresh latex might complex with proteins and amino acids and in this form it does proteins and amino acids and in this form it does not impart any adverse effect on the ageing of not impart any adverse effect on the ageing of NR. NR.
When the latex is exposed to microbial activity When the latex is exposed to microbial activity the microbes degrade the complex and release the microbes degrade the complex and release free copper which is reported to be a powerful free copper which is reported to be a powerful pro-oxidant. pro-oxidant.
MECHANISM…MECHANISM…
The degradation of the field coagulum during
storage can be prevented by treating the fresh
coagulum with a suitable bactericide.
Formalin was identified to be the best
bactericide for the above purpose
The degradation of the field coagulum during
storage can be prevented by treating the fresh
coagulum with a suitable bactericide.
Formalin was identified to be the best
bactericide for the above purpose
The following aspects were studied.The following aspects were studied.
Effect of concentration of Effect of concentration of
formalin solutionformalin solution
The optimum soaking period.The optimum soaking period.
The effect of period of storage The effect of period of storage
of the treated coagulum.of the treated coagulum.
Effect of formalin concentration on Po & PRI
30
40
50
60
70
80
0 0.25 0.5 0.75 1 1.25
Formalin concentration (%)
Po/
PR
I PRIPo
Effect of formalin concentration on Po & PRI
30
40
50
60
70
80
0 0.25 0.5 0.75 1 1.25
Formalin concentration (%)
Po/
PR
I
PRI Po
Effect of soaking period on Po & PRI
30
40
50
60
70
80
0 2 4 6 8 10 12 14 16 18
Time of immersion, h
Po/
PR
I PRIPo
Effect of formalin treatment on Po
30
40
50
60
0 10 20 30 40
Storage period, days
Po
Treated
Untreated
Effect of formalin treatment on Mooney viscosity
86
88
90
92
0 10 20 30 40
Storage period (days)
Mo
on
ey v
isco
sity
Treated
Untreated
Effect of formalin treatment on PRI
50
60
70
80
0 10 20 30 40
Storage period, days
PR
I Treated
Untreated
It was observed that soaking the It was observed that soaking the
field coagulum in 1% formalin field coagulum in 1% formalin
solution for a period of 16 hours solution for a period of 16 hours
gives sufficient protection against gives sufficient protection against
bacterial degradationbacterial degradation
It was observed that soaking the It was observed that soaking the
field coagulum in 1% formalin field coagulum in 1% formalin
solution for a period of 16 hours solution for a period of 16 hours
gives sufficient protection against gives sufficient protection against
bacterial degradationbacterial degradation
Preparation of Formalin solutionPreparation of Formalin solution
Add 100ml of formalin to 10 litres of waterAdd 100ml of formalin to 10 litres of water Prepare the required quantity of Formalin Prepare the required quantity of Formalin
solution as abovesolution as above Soak the field coagulum in the solution for one Soak the field coagulum in the solution for one
dayday Transfer the coagulum from the solution on the Transfer the coagulum from the solution on the
next daynext day The same solution can be used after filtering for The same solution can be used after filtering for
treatment of the next days crop. Extra quantity of treatment of the next days crop. Extra quantity of Formalin solution should be added to soak the Formalin solution should be added to soak the coagulum completelycoagulum completely
FarmerFarmer
Group processing facilityGroup processing facility
Block Rubber processing Block Rubber processing unitunit
The crop (field coagulum and latex coagulum)
from the Central Experimental Station, Ranni
is being subjected to the above treatment and
the material is processed at the Pilot Crumb
Rubber Factory, RRII since Jan 2004. The
treated material is brought to the factory
normally within a period of 15-25 days
The crop (field coagulum and latex coagulum)
from the Central Experimental Station, Ranni
is being subjected to the above treatment and
the material is processed at the Pilot Crumb
Rubber Factory, RRII since Jan 2004. The
treated material is brought to the factory
normally within a period of 15-25 days
0
10
20
30
40
50
60
70
80
Per
cent
age
of p
rodu
ctio
n
ISNR 10 ISNR 20 ISNR 50 OFF
2002-03
2004-05
Effect of formalin treatment on the Effect of formalin treatment on the quality of Block Rubber (PCRF)quality of Block Rubber (PCRF)
Based on the data available for one year the
cost of the treatment has been worked out to
be Rs 70/ tonne of rubber
Based on the data available for one year the
cost of the treatment has been worked out to
be Rs 70/ tonne of rubber
Environmental issues….Environmental issues….
The effect of residual formalin if any, on the effluent Treatment System of the factory is being studied
The workers handling the field coagulum at CES have been supplied with hand gloves. No complaints have been so far registered
The treated field coagulum provided a more hygienic environment in the collection centres.The mosquitoes and flies are virtually absent
The effect of residual formalin if any, on the effluent Treatment System of the factory is being studied
The workers handling the field coagulum at CES have been supplied with hand gloves. No complaints have been so far registered
The treated field coagulum provided a more hygienic environment in the collection centres.The mosquitoes and flies are virtually absent
NATURAL RUBBER – MODIFIED NATURAL RUBBER – MODIFIED FORMSFORMS
Viscosity Stabilized Rubber
Deproteinised Natural Rubber
Superior Processing Rubber
Epoxidised Natural Rubber
Chlorinated Rubber
EPOXIDISED NATURAL RUBBEREPOXIDISED NATURAL RUBBER
Gas impermeability
Resistance to hydrocarbon oils
Increased damping and good bonding
DEPROTEINISED NATURAL DEPROTEINISED NATURAL RUBBERRUBBER
Electrical and Engineering Applications
Reduced creep and stress relaxation
CHLORINATED RUBBERCHLORINATED RUBBER
Adhesives
Paints
Printing inks
Paper coating
SUPERIOR PROCESSING RUBBERSUPERIOR PROCESSING RUBBER
Low die swell, better finish
Can be effectively blended with synthetic rubbers like EPDM, SBR.
Allows wide range of extrusion temperatures and roll speeds.