Pyrolysis Gas Chromatography of Natural Rubber and Synthetic Polyisoprene

1968 ◽  
Vol 41 (2) ◽  
pp. 411-417 ◽  
Author(s):  
M. Jernejčič ◽  
L. Premru
Keyword(s):  
Gas Chromatography ◽  
Natural Rubber ◽  
Pyrolysis Temperature ◽  
Volatile Components ◽  
Pyrolysis Gas ◽  
Pyrolysis Gas Chromatography ◽  
Temperature Range

Abstract Pyrolysis gas Chromatographic isothermal and temperature programed separation of volatile components of unvulcanized natural rubber and synthetic polyisoprene was made on P-E columns Q and U. Besides identifications, relative quantitative differences between pyrolysis degradations of natural rubber and synthetic polyisoprene in pyrolysis temperature range 550°–750° C were established. It was found that the method was not suitable for an analogous study of vulcanized samples.

scholarly journals Fast Determination of the Rubber Content in Taraxacum Kok-Saghyz Fresh Biomass Using Portable Near Infrared Spectroscopy and Pyrolysis-Gas Chromatography

2021 ◽  
Author(s):  
Ying Chen ◽  
Dong Yiyang ◽  
Xiang Ma ◽  
Jiaru Li ◽  
Minmin Guo ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Infrared Spectroscopy ◽  
Natural Rubber ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Low Cost ◽  
Rubber Content ◽  
Pyrolysis Gas ◽  
Pyrolysis Gas Chromatography

Abstract Background: Taraxacum kok-saghyz (TKS), a plant native to the Tianshan valley on the border between China and Kazakhstan and inherently rich in natural rubber, inulin and other bioactive ingredients, is an important industrial crop. TKS rubber is a good substitute for natural rubber. TKS's breeding work necessitates the need to screen high-yielding varieties, hence rapid determination of rubber content is essential for the screening. Conventional analytical methods cannot meet actual needs in terms of real-time testing and economic cost. Near-infrared spectroscopy analysis technology, which has developed rapidly in the field of industrial process analysis in recent years, is a green detection technology with obvious merits of fast measurement speed, low cost and no sample loss. This research aims to develop a portable non-destructive near-infrared spectroscopic detection scheme to evaluate the content of natural rubber in TKS fresh roots. Pyrolysis gas chromatography (PyGC), was chosen as the reference method for the development of NIR prediction model. Results: 208 TKS fresh root samples were collected from the Inner Mongolia Autonomous Region of China. Near-infrared spectra were acquired for all samples. Randomly two-thirds of them were selected as the calibration set, the remaining one-third as the verification set, and the partial least squares method was successfully used to establish a good NIR prediction model at 1080-1800nm with a performance to deviation ratio (RPD) of 5.54 and coefficient of determination (R2) of 0.95. Conclusions: This study showed that portable near-infrared spectroscopy could be used with ease for large-scale screening of TKS plants in farmland, and could greatly facilitate TKS germplasm preservation, high-yield cultivation, environment-friendly, high-efficiency and low-cost rubber extraction, and comprehensive advancement of the dandelion rubber industry thereof.

The Determination of “Head-Head” and “Tail-Tail” Structures in Poly(Isoprene)S

1972 ◽  
Vol 45 (5) ◽  
pp. 1295-1302 ◽  
Author(s):  
Marjorie J. Hackathorn ◽  
M. J. Brock
Keyword(s):  
Gas Chromatography ◽  
Free Radical ◽  
Natural Rubber ◽  
Pyrolysis Gas ◽  
Pyrolysis Gas Chromatography ◽  
Chain Reversal ◽  
A Chain

Abstract Pyrolysis-gas chromatography has indicated the presence of head-head structures in free radical initiated poly(isoprene)s. Microozonolysis has confirmed the presence of both head-head (15-20 per cent) and tail-tail (4-7 per cent) structures in these polymers. These structures (which are absent in natural rubber) are present in lesser amounts in Lithium and Ziegler poly(isoprene)s (1-3 per cent). Non-equivalent amounts of head-head and tail-tail structures in particular samples indicate a chain reversal in which neither head nor tail units are involved. It has been postulated that chain reversal may occur at points of 3,4 addition.

scholarly journals Bioaccumulation study of acrylates in algae (Chlorella kessleri) by Py-GC and Py-GC/MS

2005 ◽  
Vol 3 (3) ◽  
pp. 570-582 ◽  
Author(s):  
Ladislav Halás ◽  
Andrej Oriňák ◽  
Abubaker Sharif ◽  
Monika Ádámová ◽  
Juraj Ladomerský
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Pyrolysis Temperature ◽  
Aquatic Organism ◽  
Pyrolysis Gas ◽  
Chlorella Kessleri ◽  
Pyrolysis Gas Chromatography ◽  
Acrylate Monomers ◽  
Maximum Content

AbstractAcrylate monomers methylmethacrylate (MMA) and cyclohexylmethacrylate (CHMA) bioaccumulation has been determined in aquatic organism, algae (Chlorella kessleri). Algae were collected in amount of 0.4 mg and directly injected to the pyrolytical cell. In algae bodies accumulated monomers were analysed by pyrolysis gas chromatography (Py-GC) and pyrolysis gas chromatography coupled with mass spectrometry (Py-GC/MS). Traces of the accumulated monomers in algae body can be determined after 1-, 2-, 3-weeks of incubation. Maximum content of MMA was determined after 3-week of experiment, contrariwise in the case of CHMA after 2-week exposition. Relationship with pyrolysis temperature has also been studied.

Study on Pyrolysis Behavior of Polybenzoxazine by PyGC-MS

2015 ◽  
Vol 1088 ◽  
pp. 318-321
Author(s):  
Dan Li Lin
Keyword(s):  
Gas Chromatography ◽  
Pyrolysis Temperature ◽  
Pyrolysis Gas ◽  
Pyrolysis Mechanism ◽  
Pyrolysis Gas Chromatography ◽  
Pyrolysis Behavior ◽  
Degradation Reactions ◽  
Different Temperatures ◽  
Gas Chromatography Mass Spectroscopy ◽  
Aldehyde Groups

Pyrolysis behavior of a new kind of polybenzoxazine with aldehyde groups was investigated by pyrolysis gas chromatography-mass spectroscopy (PyGC-MS) at the temperatures ranging from 450°C to 750°C. It was found from the pyrolysis chromatograms that the type and amount of its pyrolysates obviously change with pyrolysis temperature due to various pyrolysis behaviors at different temperatures. From the structures and relative contents of the pyrolysates, the pyrolysis mechanism of the polybenzoxazine was described as follows: the initial degradation reactions occurred mainly at the Cmethylene-N bond, followed by the Cphenyl-C methylene bonds.

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