2. Design and Study of Ricinoleates as processing aids and activators in rubbers…

3. What is RPA
Any material used at relatively low dosage levels, will improve processing characteristics without significantly affecting physical properties.
They also improve the physical properties such as,
Elasticity,
Flex life,
Low temp performance and,
Aid in incorporation & dispersion of pigments

4. RPA – main appc’s

5. RPA & its effects-

6. What is an Activator
- Increase the efficiency of cross-linking - Help in dispersing the sulphur and accelerator

7. Driving- FACTOR
Conventional Processing aid, petroleum based Polycyclic Aromatic Hydrocarbons (PAH) has been banned in European countries at 2009.
Stearic acid (present as activator), is a saturated fatty acid obtained from animal fat.

8. Driving- FACTOR ZnO Reduction
Car photo
ZnO Reduction
Zn can be released into the environment from rubber during production, use, and recycling of rubber goods, particularly tyres.
Harmful effect of soluble Zn-compounds to aquatic organisms.
ZnO causes a mammalian reproductive toxin
Exposure to zinc oxide in the air, result in a nervous malady called metal fume fever.
ZnS deposited on the wall of the mold, causes mold fouling.

9. AS FUTURE TECHNOLOGISTS, WE OFFER YOU SOLUTIONS…

10. EXPERIMENT
We have tried to reduce the ZnO by using a combination of metal oxide (MgO & Ca(OH)2) of varying ratios, is mixed with CASTOR OIL under microwave heating at a set frequency (1.32GHz).

11. Composition of Castor Oil
Acid Name
Average percentage Range
Ricinoleic acid
85 to 95%
Oleic acid
2 to 6%
Linoleic acid
1 to 5%
Linolenic acid
0.5 to 1%
Stearic acid
Palmitic acid
Dihydroxystearic acid
0.3 to 0.5%
Others
0.2 to 0.5%

12. Structure of Castor oil
Mono-unsaturated, 18 carbon fatty acid
(esters of hydroxy-9-octadecenoicacid)
Contains Functional groups:
1.carboxylic group
2.unsaturation
3.hydroxy group

13. Why Castor Oil Naturally obtained non-toxic Vegetable oil
Vegetable oil offers Lubricity
Other seed oils lack the HYDROXY Group
Due to this Hydroxy group-
1. Reactive
2. Offers xtra stability
3. High viscosity

14. Metal Oxide Varying ratios
COMPOUND
ZnO
MgO
Ca(OH)2 1 2 3 4 5 6 7

15. Blank Preparation MATERIALS Parts by Weight Natural Rubber 100
Zinc Oxide 3
Stearic Acid 2
Sulphur
2.5
Acc (CBS) 1

16. RX formulation MATERIALS Parts by Weight Natural Rubber 100
Activator System 5
Sulphur
2.5
Acc (CBS) 1

17. 1600C for 20mins

18. 1600C for 20mins

19. 1600C for 20mins
INFERENCE :
Both RX6 and RX7 haven’t cured, so we neglected both the samples.

20. Rheological Props (GUM cmpds)
COMPOUNDS
Ts2 mins
Tc90 mins RX
1.04
4.15
RX1
1.27
2.45
RX2
1.44
2.70
RX3
2.06
3.11
RX4
1.52
2.58
RX5
1.54
2.69
RX6
0.00
RX7
0.47
INFERENCE : Scorch time is INCREASED,
While Cure time is very much DECREASED

21. Tests for Gum cmpds : Hardness (ASTM D2240)
Tensile Properties (ASTM D412)
Tear Strength (ASTM D624)
Aging properties (ASTM D573)

22. Hardness INFERENCE : Hardness values found to decrease with
COMPOUNDS
HARDNESS (Shore A) RX 58
RX1 18
RX2 25
RX3 16
RX4
RX5 32
INFERENCE : Hardness values found to decrease with
our Activator compounds

23. TENSILE STRENGTH INFERENCE : T.S is very much lower COMPOUNDS
TENSILE STRENGTH MPa RX
22.65
RX1
1.44
RX2
4.65
RX3
2.99
RX4
2.83
RX5
4.5
INFERENCE : T.S is very much lower

24. MAX Strain % INFERENCE : profound increase in STRAIN % COMPOUNDSRX
436.5
RX1
558
RX2
587
RX3
573
RX4
615
RX5
489
INFERENCE : profound increase in STRAIN %

25. All our Activator Compounds exceeded above 600% elongation

26. MODULUS MODULUS = Resistance to extension or stiffness
COMPOUND
100% MOD
200% MOD
300% MOD RX
1.97
3.71
15.97
RX1
0.84
1.24
3.24
RX2
0.44
0.74
1.04
RX3
0.57
0.76
1.14
RX4
0.58
0.78
1.07
RX5
1.53
2.38
5.12
MODULUS = Resistance to extension or stiffness
INFERENCE : Modulus was found to be low

27. Aging Properties Aging Condition- 700C for 7 days COMPOUND
Tensile Strength MPa R
15.4
RX1
0.3
RX2
2.8
RX3
1.1
RX4
1.02
RX5
2.6

28. Tear Strength (GUM cmpds)
COMPOUNDS
TEAR STRENGTH (Kgf/mm) RX
0.264
RX1
0.731
RX2
1.839
RX3
0.701
RX4
1.051
RX5
2.076
INFERENCE :
Tear Strength usually higher for our Activator Cmpds

29. PC Formulation Benchmarked with usual mixture, ZnO - 3 phr
MATERIALS
Parts by Weight
Nitrile Rubber, NBR
100
C-Black 50
Activator system 5
Sulphur
1.5
TMTD
CBS
Benchmarked with
usual mixture,
ZnO - 3 phr
St Acid – 2 phr

30. Rheograph
1600C for 20mins

31. Rheograph
1600C for 20mins

32. Rheological Props INFERENCE : Scorch time is INCREASED,
1600C for 20mins
COMPOUNDS
Ts2 mins
Tc90 mins P
1.03
11.00
PC1
1.15
1.54
PC2
1.21
2.33
PC3
3.07
6.05
PC4
1.13
3.13
PC5
1.37
3.34
INFERENCE : Scorch time is INCREASED,
While Cure time is very much DECREASED

33. Tests for C-B filled cmpds
Hardness
Tensile Strength
Tear Strength
Swelling Index
Compression Set
Flex Cracking Resistance

34. Hardness INFERENCE : Not much change in Hardness COMPOUND
HARDNESS (Shore A) P 76
PC1 72
PC2 70
PC3 68
PC4 71
PC5 69
INFERENCE : Not much change in Hardness

35. Tensile Strength (Before aging) MPa
Aging Condition –
1000C for 22hr
COMPOUND
Tensile Strength (Before aging) MPa
Tensile Strength
(After aging) MPa P
25.57
19.61
PC1
22.45
18.20
PC2
20.72
16.97
PC3
15.37
9.57
PC4
17.25
11.23
PC5
19.50
12.60
INFERENCE : Tensile Strength is low
But % retention of our activator cmpds is high

36. Tear Strength Aging Condition – 1000C for 22hr
COMPOUND
Tear Strength
(Before aging) N/mm
(After aging) N/mm P
7.07
3.61
PC1
15.78
9.11
PC2
18.83
15.62
PC3
9.48
4.54
PC4
11.25
8.05
PC5
14.14
10.15
INFERENCE : Tear Strength and % Retention is HIGH
for our activator compounds

37. Swelling Index Swelling Index α 1 / Crosslink Density
Immersed in toluene
for 7 days
COMPOUND
SWELLING INDEX % P 69
PC1 87
PC2 80
PC3 76
PC4
PC5 77
SWELLING INDEX = (Ws – Wi)/Wi
Swelling Index α 1 / Crosslink Density

38. Compression Set SET % = (t0 – tr) / (to - ts) × 100 COMPOUND32
PC1 58
PC2 49
PC3 43
PC4 51
PC5 46
SET % = (t0 – tr) / (to - ts) × 100
INFERENCE : Set found to be lower as cross-link density is less

39. Flex Cracking resistance
SAMPLE
No of cycles for Pin-Prick to appear P
1777
PC1
>1,00,000
PC2
15,796
PC3
2481
PC4
7596
PC5
5319
INFERENCE : profound increase in Flex-Cracking resistance

40. Summary
With reduced viscosity, thereby reducing mix duration with less mech generation of heat & energy consumption reqd to breakdown rubber.
Ease of handling as processing aids is in the form of pellets.
With increased scorch time(Ts2), better Processing safety.
With shorter curing cycles, we get faster productivity.
The physical props of C-B filled cmpds was similar to the control, but this was not the case in GUM cmpds.

41. Coupling action of Veg. oil
Interacts with Rubber
molecules
Interacts with C-Black as
its surface contains Phenol,
Carboxyl, Quinone
& Lactones

43. Why MgO & Ca(OH)2 These were the acid acceptors playing a dual role :
1. Neutralization of acid-byproducts of vulcanization and;
2. Act as cross-linking agents forming weak ionic bonds.