scholarly journals Preparation and characterization of liquid natural rubber through oxidative degradation with phenyl hydrazine and benzoyl peroxide-oxygen

2021 ◽  
Vol 912 (1) ◽  
pp. 012098
Author(s):  
Tamrin ◽  
S Leny ◽  
Eddiyanto
Keyword(s):  
Natural Rubber ◽  
Benzoyl Peroxide ◽  
Oxidative Degradation ◽  
Chain Scission ◽  
Phenyl Hydrazine ◽  
Vacuum Oven ◽  
Liquid Natural Rubber ◽  
Chain Scission Reaction ◽  
Rubber Product

Abstract The aim of this research was to synthesize liquid natural rubber (LNR) from Natural rubber (SIR-20) by chain scission method in the presence of oxygen gas and difference of peroxides, phenyl hydrazine and benzoyl peroxide. The chain scission reaction was conducted in solution of xylene in close system. SIR-20 was diluted xylene before flushing with oxygen and the addition of the peroxide. The degradation oxidation by the oxygen and the peroxides was processed at 60°C for 24 hours. The degradative oxidation product was re-precipitated by adding the excess of methanol and filtrated before dried in vacuum oven 60°C for 24 hours. The dried product was characterized by Fourier Transform Infra Red (FTIR). It was found that the liquid natural rubber product successfully degraded by chain scission process as shown the change of the peak area intensity of infrared absorption. It was showed the peaks area intensity of O-H and carbonyl group of liquid natural rubber spectra increased.

scholarly journals Functionalization of Liquid Natural Rubber via Oxidative Degradation of Natural Rubber

Polymers ◽  
2014 ◽  
Vol 6 (12) ◽  
pp. 2928-2941 ◽  
Author(s):  
Suhawati Ibrahim ◽  
Rusli Daik ◽  
Ibrahim Abdullah
Keyword(s):  
Natural Rubber ◽  
Oxidative Degradation ◽  
Liquid Natural Rubber

Solid-State 13C NMR Characterization of Irradiation-Cross-Linked Natural Rubber

1987 ◽  
Vol 41 (3) ◽  
pp. 441-446 ◽  
Author(s):  
Dwight J. Patterson ◽  
Jack L. Koenig
Keyword(s):  
Solid State ◽  
Natural Rubber ◽  
Mobile Phase ◽  
Chain Scission ◽  
Structure Changes ◽  
Nmr Characterization ◽  
Cross Links ◽  
Gamma Irradiated ◽  
Trans Structure

Solid-state 13C NMR was used to characterize the structure changes produced in gamma irradiation in natural rubber. The structure of the irradiated natural rubber was found to be heterogeneous, consisting of a mobile phase and a semi-rigid phase. Cis-trans chain isomerization was detected in the mobile phase of the gamma-irradiated samples. The CP/MAS spectra of the more rigid phase contained resonances due to quaternary carbons arising from cross-links and vinyl end groups caused by main chain scission. The calculated values of β and G( X) agreed with earlier published results. Peroxide-cured natural rubber of an equivalent amount of network density showed a higher amount of trans structure than did the gamma-irradiated natural rubber.

scholarly journals Synthesis and Characterization of Liquid Natural Rubber as Impact Modifier for Epoxy Resin

2014 ◽  
Vol 55 ◽  
pp. 129-137 ◽  
Author(s):  
A.B. Ben Saleh ◽  
Z.A. Mohd Ishak ◽  
A.S. Hashim ◽  
W.A. Kamil ◽  
U.S. Ishiaku
Keyword(s):  
Natural Rubber ◽  
Epoxy Resin ◽  
Synthesis And Characterization ◽  
Liquid Natural Rubber ◽  
Impact Modifier

scholarly journals ANALISIS SIFAT TERMAL DAN UJI KELARUTAN DARI KARET ALAM SIKLIS DAN KARET ALAM CAIR SIKLIS

2018 ◽  
Vol 16 (1) ◽  
pp. 36
Author(s):  
Leni Widiarti ◽  
Basuki Wirjosentono ◽  
Eddyanto Eddyanto
Keyword(s):  
Thermal Analysis ◽  
Transition Temperature ◽  
Natural Rubber ◽  
Oxidative Degradation ◽  
Melting Transition ◽  
Scanning Calorimetry ◽  
Solubility Test ◽  
Polarity Index ◽  
Liquid Natural Rubber ◽  
Crystal Transition

Abstract. The research has done analysis of thermal properties and solubility test of Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR). Cyclic Liquid Natural Rubber (CLNR) is a cyclical natural rubber which has decreased molecular weight. Synthesis of Cyclic Liquid Natural Rubber (CLNR) do by oxidative degradation after cyclic.  Oxidative degradation after cyclic using Cyclic Natural Rubber (CNR) and phenylhydrazine reagent with flow rate 2 LMin-1 of oxygen atmosphere during 24 hours. Thermal analysis of Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR) by Differential Scanning Calorimetry (DSC),the glass transition temperature (Tg) of Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR) are 102,82  o C and 103,67 o C, the crystal transition temperature (Tc) of Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR) are 362,45 o C and 330,29 o C and the melting transition temperature ( Tm) of Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR) are 509,24 o C and 440,00 o C. Solubility test by dilute Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR) in some solvent with different properties and polarity index. Solubility test shows the results Cyclic Natural Rubber (CNR) and Cyclic Liquid Natural Rubber (CLNR)  has polarity index around 2,4 – 4,4 and 2,4 and 4,4.               Keywords: CLNR, CNR, oxidative degradation

Chain Scission Efficiency in the Oxidation of Natural Rubber Vulcanizates

1957 ◽  
Vol 30 (4) ◽  
pp. 1146-1161
Author(s):  
A. G. Veith
Keyword(s):  
Natural Rubber ◽  
Elevated Temperatures ◽  
Density Ratio ◽  
Direct Consequence ◽  
Chain Scission ◽  
Polymer Chains ◽  
Published Report ◽  
Relaxation Measurements ◽  
A Chain ◽  
Chain Scission Reaction

Abstract Natural rubber when it degrades under the action of oxygen does so primarily by a chain scission reaction. A technique has been developed by Tobolsky and coworkers for assessing the magnitude of this chain scission reaction in vulcanizates by means of continuous stress relaxation measurements. Since the result of the oxygen attack on the rubber is a chain scission reaction, the question of the efficiency of the reaction comes to mind. The influence of antioxidants is of importance in this regard as is the type of vulcanizate or network structure. This paper describes some measurements of the chain scission efficiency of a simple benzothiazolyl disulfide (MBTS) vulcanizate and the effect of several antioxidants on this chain scission reaction. Some of the complications inherent in this type of measurement are discussed. The first published report on the efficiency of the chain scission reaction in vulcanizates was given by Tobolsky, Metz, and Mesrobian in 1950. A more recent publication is that of Baxter, Potts, and Vodden in 1955. Tobolsky has interpreted the stress decay of gum vulcanizates at elevated temperatures as a direct consequence of the cutting of polymer chains of the network. The reduced stress is postulated as being equal to the chain density ratio:

Synthesis and Characterization of Segmented Block Copolymers Based on Hydroxyl-Terminated Liquid Natural Rubber and?,?-Diisocyanato Telechelics

2004 ◽  
Vol 289 (10) ◽  
pp. 927-932 ◽  
Author(s):  
Gerhard Maier ◽  
Vendula Knopfova ◽  
Brigitte Voit ◽  
Pham Huu Ly ◽  
Bui Tien Dung ◽  
...  
Keyword(s):  
Block Copolymers ◽  
Natural Rubber ◽  
Synthesis And Characterization ◽  
Liquid Natural Rubber

Synthesis and Characterization of Block Copolymer from Natural Rubber, Toluene-2,4-Diisocyanate and Poly(ξ-aprolactone) Diol-Based Polyurethane

2011 ◽  
Vol 695 ◽  
pp. 316-319 ◽  
Author(s):  
Wannarat Panwiriyarat ◽  
Varaporn Tanrattanakul ◽  
Jean François Pilard ◽  
Chuanpit Khaokong
Keyword(s):  
Block Copolymer ◽  
Natural Rubber ◽  
Soft Segment ◽  
Molar Ratio ◽  
H Nmr ◽  
Chain Cleavage ◽  
Epoxidation Reaction ◽  
Liquid Natural Rubber ◽  
New Type

A new type of polyurethane (PU) has been synthesized by using hydroxyl terminated liquid natural rubber (HTNR) and poly(e-caprolactone) (PCL) as a soft segment and toluene-2,4 diisocyanate (TDI) as a hard segment. This PU becomes a biodegradable and recyclable polymer. The PU samples were synthesized by solution polymerization. TDI/PCL polymerization was prepared in order to determine the appropriate NCO:OH ratio which evaluated from the molecular weight of derived PU and the ratios which were able to form a polymeric film. The suitable NCO:OH ratios were 0.84:1 – 1.20:1 and the Mn of the derived PUs was 3000-5500 g/mol determined by using GPC. PU from PCL-HTNR block copolymer was synthesized by varying molar ratio between PCL and HTNR. HTNR has been synthesized by epoxidation reaction and chain cleavage of natural rubber. The Mn of HTNR was in the range of 1700-8000 g/mol. 1H-NMR and FTIR were used to determine the functional group in order to verify the prepared HTNR and PU. Glass transition temperature and thermal decomposition of PU samples were investigated by using DSC and TGA, respectively.

Kinetic Study of Oxidative Scission in Natural Rubber by Wallace Plasticity Measurements

1992 ◽  
Vol 65 (1) ◽  
pp. 1-6 ◽  
Author(s):  
L. H. Gan ◽  
S. C. Ng ◽  
K. K. Chee
Keyword(s):  
Activation Energy ◽  
Kinetic Parameter ◽  
Natural Rubber ◽  
Kinetic Data ◽  
Oxidative Degradation ◽  
Chain Scission ◽  
Thermal Oxidative Degradation ◽  
Diffusion Controlled ◽  
Kinetics Of ◽  
Diffusion Controlled Reaction

Abstract The kinetics of thermal oxidative degradation of natural rubber (NR) have been studied by Wallace plasticity measurements. On the basis of the Kotliar's model of random chain scission, an expression was derived to interpret the kinetic data collected over a range of temperatures from 80 to 160°C. It has been shown that the kinetic parameter resulting from the present analysis, indeed refers to a diffusion-controlled reaction with an overall activation energy estimated to be 135 ± 6 kJ · mol−1. In addition, the implications of plasticity retention index, which measures the oxidizability of NR, are discussed.

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