Curing and Mechanical Properties of a Tyre which is made of a Rubber Compound Based on Sheet Rubber

Manufacture from Ammonia Preserved Latex

R.G.N LakmaliPlastic and Rubber Institute,

Sri Lanka

Out Line•Introduction•Research Objectives•Methodology•Result and Discussion•Conclusion•References•Acknowledgement

INTRODUCTION

•Natural Rubber Latex is the majorsynthesized commercial product which isobtained from the rubber (Heveabrasiliensis)tre•There are different types of rubber madefrom field latex for many purposes

They are

•Crepe rubber•Ribbed Smoke Sheet (RSS)•Technically Specified Rubber(TSR)• Scrap Rubber

•Ribbed smoked sheet is the most popular and is available for volume consumption

•RSS is consists of coagulated rubber sheets, dried using smoke•RSS is mainly used in automobile tyre manufacturing

RSS Manufacturing ProcessCollection of Latex

Standardization

Coagulation

Milling

Smoking

Sorting,Greading and Packing

This study was carried out to study theprocessing characteristic of latex into RSSrubber and the raw rubber properties andcuring characteristics of rubber compositesmade out of ammoniated natural rubberlatex in comparison with the sameproperties of sheet rubber made out ofsodium sulphite

Research objectives•To study the Raw rubber properties of ammonia preserved latex on Ribbed Smoke Sheet manufacturing

•To study the curing characteristic of ammonia preserved latex on Ribbed Smoke Sheet

•To study the properties of rubber compound which made from ammonia preserved latex on Ribbed Smoke Sheet to manufacturing new tyre compound

Methodology

Waiting

period of

latex

(days)

Preservative and its concentration on latex

Control Na2SO3

(0.05%)

NH3 (0.05%) NH3 (0.10%) NH3 (0.15%) NH3 (0.20%)

0 C0 Na5 N 0.05-0 N 0.10-0 N 0.15-0 N0.20-0

1 - - N 0.05-1 N 0.10-1 N 0.15-1 N0.20-1

2 - - N 0.05-2 N 0.10-2 N 0.15-2 N0.20-2

Raw Rubber Properties

•Volatile Matter Content(VMC)•Mooney Viscosity•Un-aged Rapid Plasticity (P0) and Plasticity Retention Index (PRI)

•MINITAB software and Factor factorial CRD design were used for this experimental design under General Liner Method(GLM) to analysis purposes

Result and Discussion

Treatment(Concentration) No of day Mean VM

Control(0) 1 0.498153283

0.05 % Na2SO3 1 0.610067984

0.05% NH3 1 0.624707184

0.1% NH3 1 0.628775747

0.15% NH3 1 0.613766587

0.15% NH3 2 1.329399675

0.2% NH3 1 0.797483842

0.2% NH3 2 0.726557103

0.2% NH3 3 0.43054807

VMC for each preservative concentration levels and days

R-Sq Value = 99.98%(R-Sq >80%)

•The volatile matter content is dependingon the ammonia concentration of thesheet and with the increasing of theammonia concentration the VMC isincreased.

treatmentday

0.200.150.100.050.00321321321321321

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0.0

Mea

n of

VM

(%)

VMC under different preservative concentration levels and days

Treatment(Concentration) No of day Mooney ViscosityControl(0) 1 75

0.05 % Na2SO3 1 77

0.05% NH3 1 76

0.1% NH3 1 75

0.15% NH3 1 79

0.15% NH3 2 79

0.2% NH3 1 74

0.2% NH3 2 76

0.2% NH3 3 77

Mooney Viscosity For Each Preservative Concentration Levels And Days

R-Sq Value = 72.12%(R-Sq <80%)

•There for the samples have not the effect onits mooney viscosity by preservation of sheetwith ammonia. The mooney viscosity is notdepending on the ammonia concentration ofthe sheet.

TreatmentDate

0.200.150.100.050.00321321321321321

80

70

60

50

40

30

20

10

0

Mea

n of

Moo

ny u

nit

Mooney Viscosity under different preservative concentration levels and days

Treatment(Concentration) No of day PRIControl(0) 1 87.40

0.05 % Na2SO3 1 93.80

0.05% NH3 1 94.85

0.1% NH3 1 91.03

0.15% NH3 1 81.16

0.15% NH3 2 81.46

0.15% NH4 3 81.63

0.2% NH3 1 79.00

0.2% NH3 2 82.11

0.2% NH3 3 85.20

PRI for Each Preservative Concentration Levels and Days

R-Sq Value = 99.81%(R-Sq >80%)

•the samples have the effect on its PRI bypreservation of sheet with ammonia.• With the increasing of ammoniaconcentration the PRI has dropped down ofeach sheet.

Due to the over drying and heating, phenolic compounds whendrying sheets, are affect for these incidents.

TreatmentDate

0.200.150.100.050.00321321321321321

100

80

60

40

20

0

Mea

n of

PRI

PRI under different preservative concentration levels and days

CONCLUSION

Raw rubber properties which are Volatilematter content (VMC) and Plasticity RetentionIndex (PRI) affected by the preservation withammonia

•PRI will be dropped•Mooney viscosity is not affected

REFFERENCES

•Karunanayake, L LeelaWanigatunga, Perera, P L Senanayake C and SriyanthiWeeraman, H. Raw Rubber and Latex Properties of ClonalRubber. Bulletin of the Rubber Research Institute ofSriLankaVol40,pp17-24, (1999)

•Chukwu, M NIdiagha,J A and Ihuezor, M O. Effect of Acid Coagulation Level on The Plasticity Retention Index (PRI) of Natural Rubber,Multidisciplinary Journal of Research DevelopmentVol15 No 3(2010)

•KulchanatPrasertsit, NamthipRattanawan, and JuraivanRatanapisit. Effects of wood vinegar as an additive for natural rubber products, Songklanakarin J. Sci. Technol.Vol33 (4), pp (2011)

ACKNOWLEDGEMENT

•Dr.Susantha Siriwardhane,Internal SupervisorHead, Department of Chemical and ProcessEngineering,Rubber Research Institute (RRI) atRathmalana

•All members of Plastic and Rubber Instituteand RRI