STABILIZATION OF RAW DIENIC SYNTHETIC RUBBER POLYMERS

2011 ◽  
Vol 84 (3) ◽  
pp. 273-295 ◽  
Author(s):  
Joseph A. Kuczkowski
Keyword(s):  
Hydrogen Atom ◽  
Transformation Products ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Highly Active ◽  
Synthetic Rubber ◽  
Alkyl Groups ◽  
Polymer Properties ◽  
Polybutadiene Rubber ◽  
Styrene Butadiene

Abstract The mechanism of rubber polymer autoxidation is briefly reviewed with an emphasis and an appreciation for what these uninhibited free radical reactions can do to polymer properties and quality. Significant differences between hydrocarbon and rubber oxidation are discussed. Differences in polymer substructure are described which affect the mode of oxidation as well as the choice of stabilizer to protect these materials. An explanation of color formation and color prevention for 2,6-dialkyl-4-methylphenols is provided which also includes a discussion of how their oxidized transformation products interact with the rubber polymer. Additional factors that affect polymer quality include proxidative effects of the stabilizer, oxygen diffusion, and the formation of gel. Studies which varied the steric bulk of the alkyl groups in the 2,6 position were conducted to optimize the antioxidant activity of this system in its function in the hydrogen atom donor—hydrogen atom acceptor mechanism of stabilization. A description of the preparation and activity impact of the secondary antioxidant synergist Wingstay® SN-1 is included. Finally, the discovery of highly active 2,6-di(alkylthiomethyl) substituted phenols is described which led to the discovery of Wingstay® K and its contained synergist methylene-bis(dodecylsulfide). This material is a highly persistent auto synergistic stabilizer which is outstanding for the protection of emulsion-styrene butadiene rubber when used 50/50 with Wingstay® 29. When used by itself in polybutadiene rubber polymers, it is highly effective against the effects of oxidation and also for the prevention of gel formation and Mooney viscosity changes.

scholarly journals Experimental Investigation on the Use of Waste Elastomeric Polymers for Bitumen Modification

2020 ◽  
Vol 10 (8) ◽  
pp. 2671
Author(s):  
Sadegh Yeganeh ◽  
Mahmoud Ameri ◽  
Davide Dalmazzo ◽  
Ezio Santagata
Keyword(s):  
Permanent Deformation ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Waste Products ◽  
Expected Performance ◽  
Polybutadiene Rubber ◽  
Modified Binders ◽  
Experimental Findings ◽  
Styrene Butadiene ◽  
Bitumen Modification

The study described in this paper focused on the possible use of waste products coming from the production of styrene–butadiene rubber (SBR) and polybutadiene rubber (PBR), as bitumen modifiers. Modified binders containing these products were prepared in the laboratory with different polymer dosages and were thereafter subjected to the evaluation of empirical and rheological properties. For comparative purposes, the study also considered SBR and PBR products of premium quality. Ageing effects were also taken into account by means of proper laboratory simulations. Obtained results indicated that the two types of polymer (SBR and PBR) have completely different effects on the rheology and expected performance of the resulting modified binders. In particular, while the two polymers showed similar effects in terms of resistance to permanent deformation, the SBR products proved to be superior from the viewpoint of fatigue resistance. However, only minor differences were found when comparing the effects produced by premium quality and waste polymers. As a result of the experimental findings, it was concluded that the use of waste SBR polymers can be an attractive solution for the production of affordable modified binders.

Accelerator Action of Certain Heterocyclic N-Thiocarbamylsulfendialkylamides

1962 ◽  
Vol 35 (3) ◽  
pp. 644-651 ◽  
Author(s):  
I. I. Éitingon ◽  
M. S. Feldshtein ◽  
D. M. Pevzner
Keyword(s):  
Considerable Extent ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Piperazine Derivatives ◽  
Highly Active ◽  
Initial Stage ◽  
Vulcanization Kinetics ◽  
Styrene Butadiene

Abstract 1. The accelerator activities of heterocyclic N-thiocarbamylsulfendialkylamides based on piperidine, morpholine, and piperazine were investigated; it was found that compounds of this type are highly active accelerators of the vulcanization of natural and styrene butadiene rubber stocks, inducing rapid crosslinking and giving rubbers of higher modulus than the usual vulcanization accelerators. 2. The vulcanization kinetics in presence of these heterocyclic N-thiocarbamylsulfendialkylamides depends to a considerable extent on the nature and number of hetero atoms in the accelerator molecule. Morpholine and piperazine derivatives have a slower effect at the initial stage of vulcanization than the corresponding piperidine derivatives, and confer greater resistance to premature vulcanization of the rubber stocks.

scholarly journals Mechanical and morphology characteristics of natural rubber-styrene butadiene rubber (NR-SBR) blends in the presence of natural microbentonite

2021 ◽  
Vol 912 (1) ◽  
pp. 012072
Author(s):  
B Wirjosentono ◽  
A H Siregar ◽  
D A Nasution
Keyword(s):  
Natural Rubber ◽  
Rubber Tree ◽  
Weight Ratio ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Mineral Oils ◽  
Synthetic Rubber ◽  
Styrene Butadiene ◽  
Morphology Characteristics ◽  
Xylene Solution

Abstract Natural rubber (NR) has been the world renewable natural elastomer produced mainly in South East Asia from the sap of rubber tree (hevea brasiliensis). However it only exported to manufacturing countries for production of various engineering and specialty rubber products. Blending of the natural rubber with synthetic rubber such as styrene butadiene rubber (SBR) is a mean to improve engineering specification of the NR, especially due to exposure of mineral oils during its service life. Whereas natural microbentonite functions not only as filler but also as coagulant breaker in both SIR-10 and SBR matrices, which improves miscibility of the blends. In this work blending of Indonesian natural rubber (NR: SIR-10) with styrene butadiene rubber (SBR) were carried out in reflux reactor in xylene solution in the presence of various loading of natural microbentonite as fillers. Miscibility of the blends were measured from their mechanical properties as well as morphology of their fracture surfaces using electron microscopy (SEM). It was found that optimum loading of microbentonite in the NR/SBR (weight ratio: 50/50) blend was 3 per hundred rubber (phr), which showed good adhesion of the rubber matrices onto the filler surface and without any agglomeration.

Characterization of Natural Rubber (NR), Polybutadiene Rubber (BR) and Styrene-Butadiene Rubber (SBR) Blends Cured in a Vulcanization System

2021 ◽  
Vol 1039 ◽  
pp. 51-64
Author(s):  
Muhsin Jaber Jweeg ◽  
Zaid G.A. Al-Jlaihawi
Keyword(s):  
Tensile Strength ◽  
Carbon Black ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Maximum Value ◽  
Polybutadiene Rubber ◽  
Maximum Tensile Strain ◽  
Number Of Cycles ◽  
Styrene Butadiene

In this work, the mechanical properties of three types of dough rubber NR, NR/BR, and NR/SBR have been investigated using five percentages of materials fill (30, 40, 50, 60, and 70) pphr. Carbon black was used as a filler material. The tensile test was achieved with 300% elongation and strain rates of (100, 200, 300, 400, and 500) mm/min. The tensile strength results indicate that the maximum value of tensile strength for NR Dough carbon black 60 pphr reaches 23.2 MPa; the maximum tensile strain of NR dough (carbon black 50 pphr) reaches 805.5%, and the modulus of elasticity with carbon black 70 pphr reaches 4.3 MPa. It was found that the compression strength decreases with increasing the carbon black, and the maximum value of compression set at NR dough (carbon black 30 pphr) reaches 29.3%. Fatigue crack growth was achieved according to ASTM D 813 for rubber testing. The minimum value of fatigue strength dough (carbon black 70 pphr) reaches 68 (IRHD). For NR dough (carbon black 30,40,50 pphr) reaches 3.5 mm at the number of cycles 15000 cycle. Finally, the maximum hardness of NR.

Effect of Epoxidized Palm Oil (EPO) on Tensile Properties and Density of Rubber Compounding

2013 ◽  
Vol 812 ◽  
pp. 216-220 ◽  
Author(s):  
Mohd Nasir Anis Nazurah ◽  
Ahmad Zafir Romli ◽  
M.A. Wahab ◽  
Mohd Hanafiah Abidin
Keyword(s):  
Tensile Strength ◽  
Palm Oil ◽  
Abrasion Resistance ◽  
Renewable Resource ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Elongation At Break ◽  
Synthetic Rubber ◽  
Epoxidized Palm Oil ◽  
Styrene Butadiene

Epoxidized palm oil (EPO) can act as processing oil has the potential of non toxic, degradable, renewable resource and as the alternative safe process oils in rubber compounding. Epoxidized palm oil is used as some of additives in rubber compounding to provide function of softener or stabiliser thus, improve properties of rubber compounding performance. Rubber that is used in this study is styrene butadiene rubber (SBR); a synthetic rubber copolymer consisting of styrene and butadiene. SBR also has good abrasion resistance and good aging stability when protected by additives. Compared to natural rubber, SBR has better processability, heat aging and abrasion resistance but inferior elongation, hot tear strength, hysteresis, resilience and tensile strength. This study is focusing on the effect of EPO without the addition of carbon black into the compound via tensile and density test. This is very important as to study the physical and mechanical interaction between SBR and EPO without the influence of other fillers. Different loading of oil were used at 25 pphr, 30 pphr. 35 pphr, 40 pphr and 45 pphr in the compounding process as processing aid. EPO35 which contain 35 pphr of EPO shows the highest value of tensile strength which is 2.2 MPa. The vulcanizate that contain 30 pphr of EPO shows the highest value for Youngs modulus which is 0.22 MPa while the elongation at break increased as the oil loading increased. The highest value for density is 0.979 g/cm3 for the vulcanizate contain 25 pphr of EPO. The results indicates that EPO is potential to replace other processing oils as renewable resource and safe to human.

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