Influence of Processing Oil Based on Modified Epoxidized Vegetable Oil with N-Phenyl-p-Phenylenediamine (PPD) on Extrusion Process Behaviors of Natural Rubber Compounds

2015 ◽  
Vol 659 ◽  
pp. 423-427 ◽  
Author(s):  
Chalida Moojea-Te ◽  
Adisai Rungvichaniwat ◽  
Kannika Sahakaro

Rubber processing oil based on modified epoxidized vegetable oils (m-EVO) was prepared by a reaction of epoxidized palm oil EPO) or epoxidized soybean oil (ESBO) with N-Phenyl-ρ-phenylenediamine (PPD) at a mole ratio of 1:0.5. The comparison of m-EVO with aromatic oil (Treated distillate aromatic extract, TDAE) on extrusion process behaviors (output rate, extrusion rate, screw efficiency, heat generation, die swell, extrudate appearance) of carbon black (N330) filled natural rubber (NR) compound was made. It was found that the mooney viscosity of m-EVO based natural rubber compounds are slightly higher than that of the TDAE based natural rubber compound (ML(1+4)100°C: m-ESBO 65.5±0.7; m-EPO 59.7±0.2; TDAE 56.5±1.0), which probably due to the poorer filler dispersion in the compounds. The extrusion process behaviors for output rate (g/min: m-ESBO 191.0±0.6; m-EPO 191.2±0.4; TDAE 195.5±0.6), extrusion rate (cm3/min: m-ESBO 179.6±0.6; m-EPO 183.2±0.4; TDAE 186.4±0.6) and screw efficiency (%: m-ESBO 30.8±0.6; m-EPO 31.4±0.4; TDAE 32.0±0.6). All the three compounds show similar extrusion process behaviors in which the TDAE based compounds shows a marginal higher values than the m-EVO as its lower mooney viscosity lead to a better flow. The m-EPO and m-ESBO based natural rubber compounds show very similar extrusion process behaviors. The heat generation (°C: m-ESBO 61.0±0.8; m-EPO 62.1±0.4; TDAE 63.1±1.0) and die swell (%: m-ESBO 11.0±0.7; m-EPO 11.0±0.5; TDAE 12.7±0.3) of the m-EVO based natural rubber compounds are slightly lower than those of the TDAE based natural rubber compound. As there are no significant differences in the extrusion process behaviors, with respect to extrusion process, m-EVO can be used to replace TDAE oil.

2017 ◽  
Vol 744 ◽  
pp. 282-287
Author(s):  
Sarawut Prasertsri ◽  
Sansanee Srichan

This research aimed to develop the formulation of natural rubber filled with carbon black, silica and calcium carbonate for rubber calf nipple application. The reverse engineering was performed on the calf nipple product to analyze the rubber type and component by using Soxhlet extraction, thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) techniques. Furthermore, mechanical properties were examined to act as benchmark for the rubber compound design. The results showed that rubber component in the nipple product was natural rubber, whereas two filler types revealed as carbon black and calcium carbonate with 10 and 35 of the total weight. In addition, rubber nipple showed the hardness of 46±1 Shore A and tensile strength of 5.3±0.60 MPa. From the investigation of the properties of developed rubber compounds in this work, it was found that the mechanical properties depended on type and content of filler. The required mechanical properties of vulcanizates were achieved at 20 phr of carbon black (N330), 20 phr of silica and 120 phr of calcium carbonate.


1960 ◽  
Vol 33 (3) ◽  
pp. 810-824 ◽  
Author(s):  
H. C. Baker ◽  
R. M. Foden

Abstract SP rubbers give greater latitude in extrusion and calendering processes by extending the range of operating conditions and giving greater scope for compounding for good physical properties. Compounds based on SP rubbers extrude smoothly with lower die swell at lower temperatures and higher viscosities. Greater productivity is obtained through the faster screw speeds which are possible with SP rubbers in many types of compound. SP rubber compounds calender with greater conformity to gage, greater ease of handling and control of shrinkage of the calendered sheet, at temperatures 10° C lower than normal. The firmer stocks given by SP rubbers and their greater resistance to degradation on milling lead to reduced wastage of unvulcanized compound in the factory, while the stricter control of processing permitted by SP rubbers results in a lower percentage of rejected articles. Evaluation of an experimentally produced SP 90 crepe has indicated the potentialities of a concentrated form of SP rubber as a more efficient processing aid than crosslinked SBR 1009 with NR and SBR.


2013 ◽  
Vol 2 (4) ◽  
pp. 38-42
Author(s):  
Indah M.S. Sitorus ◽  
Yudha Widyanata ◽  
Indra Surya

By using a semi-efficient sulphur accelerated vulcanization system, an investigation of the effect of  alkanolamide on cure characteristics and hardness  properties of kaolin-filled natural rubber compounds was carried out. Alkanolamide was synthesized  from Refined Bleached Deodorized Palm Stearin (RBDPS) and diethanolamine. Alkanolamide was incorporated into the kaolin filled-natural rubber compound at 1.0; 3.0; 5.0 and 7.0 Parts per-Hundred RubbeR (phr). It was found that alkanolamide gave shorter scorch time and cure time. Alkanolamide also exhibited higher torque different,  crosslink density, and hardnessup to 5.0 phr and then decreased with further increasing the loading of alkanolamide.


2014 ◽  
Vol 1024 ◽  
pp. 175-178
Author(s):  
Mazlina Mustafa Kamal ◽  
Dayang Habibah Abang Asmawi

Since the introduction of the so-called Green Tyre concept, in the early 90ies, the use of silica as reinforcing fillers has spread and grown worldwide. The general advantages of silica as reinforcing filler over carbon black filler are better rolling resistance by achieving at least equal wet traction while tread wear should not be adversely affected. One way to obtain both low rolling resistance and high wet traction is indeed, to use precipitated silica together with solution polymers in tyre treads. The benefits of reinforcement by silane coupled silicas, in certain blends of solution styrene –butadiene rubber (SBR) and butadiene rubber (BR), were recognized by major tyre manufacturer. However, the use of silica compounds entails considerable disadvantages in terms of raw material costs and processability (before vulcanization). These difficulties include higher compound Mooney Viscosity (ML1+4) that increases upon storage, short scorch time and environmental problems related to alcohol evolution. The high viscosity and poor processability in silica filled rubber compounds are believed to be associated with silica reaggregation (self aggregation) after rubber compounding. The study has been made of the effect of increased mixing stage and dispersion agent in rubber on uncured properties of the Silica Filled Epoxidised Natural Rubber Compounds. In this experiment, two orders of mixing were considered (1) Two Stages Mixing and (2) Three Stages Mixing. Results showed that filler dispersion, Mooney Viscosity and Payne Effect was influenced by the degree of mixing. The incorporation of dispersion agents in the compounds also resultant in the similar manner. It is believed that the dispersion agent could coat the silica surfaces as they are being broken down during the mixing and then stabilize the dispersed structure by stearically preventing silica reagglomeration.


2018 ◽  
Vol 38 (8) ◽  
pp. 723-729 ◽  
Author(s):  
K. Anas ◽  
Samson David ◽  
R.R. Babu ◽  
M. Selvakumar ◽  
S. Chattopadhyay

AbstractThe dynamic deformation of a viscoelastic material can cause heat generation. This heat generation is an aspect of energy dissipation. The present paper investigates the contribution of crosslink type and density on energy dissipation mechanism in natural rubber compounds. The influences of these elements are investigated using a very high frequency (VHF) analyzer (VHF 104) and a dynamical mechanical analyzer (DMA). The VHF 104 analyzer follows transmissibility and vibration isolation principle, whereas DMA works on dynamical mechanical the deformation principle. Higher crosslink density promotes lower heat generation in rubber compounds. Tanδinterpretation for energy dissipation characteristics of rubbery compounds should be done judiciously to avoid wrong interpretations. Polysulfidic linkages show higher damping ratios (ζ) than monosulfidic or disulfidic linkages due to their dissipative nature. The natural frequency (ωn) of a system at a given mass is the function of its crosslink density.


2013 ◽  
Vol 844 ◽  
pp. 221-224 ◽  
Author(s):  
Hasleena Boontawee ◽  
Charoen Nakason ◽  
Azizon Kaesaman ◽  
Anoma Thitithammawong ◽  
Sopa Chewchanwuttiwong

Modified benzyl esters from coconut, palm, and soybean oil were used as alternative rubber processing oil to replace distillate aromatic extract oil (DAE). The effect of benzyl esters on mixing, curing properties, polymerfiller interaction and Mooney viscosity was investigated in silica filled natural rubber compound. Benzyl ester oil was found to be effective processing oil with decreasing of mixing energy and Mooney viscosity. Furthermore, it was found that coconut and palm benzyl esters showed higher torque difference than the aromatic oil filled compound. Also, benzyl ester oil gave similar level of cure time and dynamic properties compared with the rubber compound with aromatic oils.


2015 ◽  
Vol 1125 ◽  
pp. 50-54 ◽  
Author(s):  
Bryan B. Pajarito

Rheometric properties of rubber compounds are usually monitored with time during the course of vulcanization at constant temperature. The measured vulcanization characteristics of rubber compound are used for quality control and evaluation of raw materials and product formulations. With the high number of ingredients used in typical formulations, it is important to identify ingredients which significantly affect the vulcanization characteristics of a rubber compound. This study reports the vulcanization characteristics of a natural rubber compound at 60 °C as function of ingredient loading. Rubber sheets are compounded according to a 212-8 fractional factorial design of experiment, where ingredients are treated as factors varied at low and high loadings. Vulcanization curves, which are time plots of elastic torque S’, viscous torque S”, and tan δ = S”/S’, are measured for each rubber sheet using a moving die rheometer. The following responses are then determined from the vulcanization curves for data analysis: minimum elastic torque ML, maximum elastic torque MH, torque difference ∆S = MH – ML, scorch time ts1, cure time t’90, cure rate index CRI = 100/ (t’90 – ts1), S” and tan δ values at ML and MH. Analysis of variance (ANOVA) shows used oil to be the main ingredient affecting vulcanization of the natural rubber compound (ML, MH, ∆S, ts1, S” at ML and MH), followed by sulfur (MH, ∆S, CRI), calcium carbonate CaCO3 (S” at ML, tan δ at MH) and diphenylguanidine DPG (ts1). High loading of used oil lowers the elastic and viscous response of the rubber compound, while increases the time for scorch. Increased loading of sulfur significantly enhances the elastic torque and cure rate of the compound. High loading of CaCO3 improves the viscous response, while DPG significantly shortens the scorch time of the rubber compound.


2015 ◽  
Vol 659 ◽  
pp. 414-417 ◽  
Author(s):  
Nattanee Dechnarong ◽  
Adun Nimpaiboon ◽  
Jitladda Sakdapipanich

Silica and carbon black have been widely used as the main reinforcing fillers for improving the properties of natural rubber (NR). In a silica-filled rubber compound, it is known that the low compatibility between NR and silica affects the mechanical properties of rubber products. In order to overcome this drawback, the functionalized saponified NR (FSPNR) was carried out by grafting acrylamide (AM) onto the saponified NR (SPNR) under UV radiation as a continuous process. An increasing in the bound rubber content and Mooney viscosity was found as an increasing AM content. Storage modulus at low strain amplitude of the silica-filled FSPNR was lower than that of the raw NR. In addition, SEM micrographs showed the good dispersion of silica in FSPNR. These confirmatory evidences indicate the improvement of rubber-filler interaction and the reduction of filler-filler interaction by functionalization under UV radiation.


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