scholarly journals Stretch-induced Wettability Changes of the Superhydrophobic Microstructured Vulcanized Rubber Surface

2018 ◽  
Vol 61 (6) ◽  
pp. 348-353 ◽  
Author(s):  
Riku TAMURA ◽  
Yuji HIRAI ◽  
Hiroyuki MAYAMA ◽  
Yasutaka MATSUO ◽  
Takahiro OKAMATSU ◽  
...  
Keyword(s):  
Vulcanized Rubber ◽  
Rubber Surface

Rationalization of the Hardness Testing of Rubber

1936 ◽  
Vol 9 (1) ◽  
pp. 83-94
Author(s):  
J. R. Scott
Keyword(s):  
Theoretical Basis ◽  
Practical Significance ◽  
Reverse Direction ◽  
Hardness Testing ◽  
Dead Weight ◽  
Rubber Industry ◽  
Hardness Tester ◽  
Vulcanized Rubber ◽  
Rubber Surface ◽  
Compression Characteristics

Abstract The object of this paper is to draw attention to the present unsatisfactory state of the hardness testing of vulcanized rubber and the need for standardization of this test, and also to present some results of an investigation into the theoretical basis of hardness testing and the practical significance of hardness measurements. In this paper the word “hardness” will be used in the sense generally accepted in the rubber industry, that is, to denote resistance to indentation. The most commonly used types of hardness tester measure hardness in terms of the depth of the indentation made by a rigid ball or blunt pin pressed into the rubber by either a dead weight or a spring. The reading given by such an instrument, usually termed the hardness number, must depend on several variable factors, namely (1) the dimensions of the ball or pin; (2) the weight used to press it into the rubber, or the compression characteristics of the spring in the case of spring-loaded instruments; (3) the direction of the scale of the instrument, i. e., whether the reading increases with the depth of indentation, as in the Pusey-Jones Plastometer, or in the reverse direction, as in the Durometer; (4) the units in which the indentation is measured, i. e., whether in 100ths of a millimeter, 1000ths of an inch, or arbitrary units. In addition to these factors relating to the instrument, the reading must also depend on the dimensions of the rubber test-piece, especially its thickness, the nature of the rubber surface, and the period for which the ball or plunger is pressed on to the rubber before the reading is taken.

scholarly journals Desulfurization of Vulcanized Rubber Particles Using Biological and Chemical Methods

2020 ◽  
Author(s):  
Cristian Valdés ◽  
Camila Hernández ◽  
Rodrigo Morales-Vera ◽  
Rodrigo Andler
Keyword(s):  
Morphological Changes ◽  
Chemical System ◽  
Cross Linking ◽  
Chemical Methods ◽  
Vulcanized Rubber ◽  
Rubber Waste ◽  
Rubber Surface ◽  
Rubber Recycling ◽  
First Time ◽  
Energy Disperse Spectroscopy

Abstract Currently, recycling or degradation treatments for tires are an enormous challenge. Despite efforts to dispose of or recycle it, rubber waste is increasing year by year worldwide. To create a rubber-recycling system, several researchers have proposed tire desulfurization. In this study, we compare two methods: one biological, using Acidobacillus ferroxidans in shake 250 mL flask experiments, and one chemical using, for the first time, microwaves and an aqueous solution. The results of these methods were analyzed through sulfate quantification, cross-linking differences, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy disperse spectroscopy (SEM-EDS). We observed that the amount of sulfates generated by the chemical system was 56 mg / L, which was 10-times higher than the biological system, which generated 5.3 mg / L. Similarly, after cross-linking studies, a 36% higher decrease after the chemical treatment was observed. When using FTIR analysis, the disappearance of characteristic bands corresponding to functional groups containing sulfur bonds was observed by treating the sample with both desulfurization mechanisms. Morphological changes on the rubber surface structure was also demonstrated by SEM-EDS analysis with the appearance of holes, cracks and changes in the porosity of the material. This work analyzed two different non-aggressive desulfurization mechanisms that might be used as sustainable methods for rubber recycling processes.

scholarly journals Desulfurization of Vulcanized Rubber Particles Using Biological and Couple Microwave-Chemical Methods

2021 ◽  
Vol 9 ◽  
Author(s):  
C. Valdés ◽  
C. Hernández ◽  
R. Morales-Vera ◽  
R. Andler
Keyword(s):  
Morphological Changes ◽  
Chemical System ◽  
Cross Linking ◽  
Chemical Methods ◽  
Vulcanized Rubber ◽  
Rubber Waste ◽  
Rubber Surface ◽  
Rubber Recycling ◽  
First Time ◽  
Energy Disperse Spectroscopy

Currently, recycling or degradation treatments for tires are an enormous challenge. Despite efforts to dispose of or recycle it, rubber waste is increasing year by year worldwide. To create a rubber-recycling system, several researchers have proposed tire desulfurization. In this study, we compare two methods: one biological, using Acidobacillus ferroxidans in shake 250 ml flask experiments, and one chemical using, for the first time, microwaves and an aqueous solution. The results of these methods were analyzed through sulfate quantification, cross-linking differences, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy with energy disperse spectroscopy (SEM-EDS). We observed that the amount of sulfates generated by the chemical system was 22.40 (mg/L)/g of rubber, which was 22-times higher than the biological system, which generated 1.06 (mg/L)/g of rubber. Similarly, after cross-linking studies, a 36% higher decrease after the chemical treatment was observed. When using FTIR analysis, the disappearance of characteristic bands corresponding to functional groups containing sulfur bonds and metal oxides were observed by treating the sample with both desulfurization methods. Morphological changes on the rubber surface structure was also demonstrated by SEM-EDS analysis with the appearance of holes, cracks and changes in the porosity of the material. This work analyzed two different non-aggressive desulfurization approaches that might be used as methods for rubber recycling processes.

Evaluation of 18 Year-Service Lifetime of NR-SBR Lining

2011 ◽  
Vol 291-294 ◽  
pp. 2914-2917
Author(s):  
Jan Racek ◽  
Eva Kalabisová
Keyword(s):  
Charge Compensation ◽  
Crosslinking Density ◽  
Polymer Coatings ◽  
Photoelectron Spectra ◽  
Shore Hardness ◽  
Energy Beam ◽  
Vulcanized Rubber ◽  
Rubber Surface ◽  
The Stability

Our recent high resolution core level and valence level X-ray photoelectron spectra (XPS) of Natural-Styrene Butylene Rubber (NR/SBR) demonstrated much narrower linewidths than previously obtained on rubbers or other polymer coatings. This improvement is due to low-current, low-energy beam flood gun charge compensation on non-conductor rubbers. The different charging has compensated on the rough surface and in the bulk of sponge structure in depth 50 Å of rubber sample. Despite residual charging has occurred on the surface which is apparent in C1s and O1s shoulder on its right side of the peak shape. Carbon groups such as C-H, C-C, C=C cannot be easily differentiated by their principal C(1s) peak chemical shift. Carbon black fillers seem to behave quite differently in the rubber-curing reaction. The stability of vulcanized rubber with sulfur curing system was studied in components of C(1s), O(1s), S(2p) regions which represented appropriate estimation of changes of crosslinked with sulfide bonds on rubber surface. The connection between the Shore hardness of rubber and the presence of carbonyl and sulphonyl groups was apparent. A model has been proposed for the degradation of the crosslinking density of rubber after long term exposure.

Surface Modification on Vulcanized Rubber by DBD Plasma

2015 ◽  
Vol 1119 ◽  
pp. 375-378
Author(s):  
Pongsopa ◽  
Kanchaya Honglertkongsakul ◽  
Pattira Homhuan
Keyword(s):  
Contact Angle ◽  
Treatment Time ◽  
Input Voltage ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Electrode Gap ◽  
Dbd Plasma ◽  
Vulcanized Rubber ◽  
Rubber Surface ◽  
Infrared Spectrometer

Vulcanized rubber surface was modified by dielectric barrier discharge (DBD) plasma system. The hydrophilic surface can be achieved in the shortly treatment and confirmed by contact angle measurement. The increasing hydrophilic group on rubber surface was monitored by Attenuated total reflectance fourier transform infrared spectrometer called as ATR-FTIR. The surface roughness was investigated to decrease from 202.13 to 82.02 nm after DBD plasma at treatment time 180s.The optimum conditions for making contact angle lower to 22 degree by DBD plasma treatment in this work were; treatment time, 15 s; input voltage on a neon sign transformer, 200 V; electrode gap, 6 mm.

Standardization of Ozone Testing

1931 ◽  
Vol 4 (1) ◽  
pp. 13-23
Author(s):  
E. P. W. Kearsley
Keyword(s):  
Film Formation ◽  
Wave Length ◽  
Short Wave ◽  
Progressive Deterioration ◽  
Vulcanized Rubber ◽  
Gutta Percha ◽  
Short Wave Length ◽  
Rubber Surface ◽  
The Many

Abstract THE progressive deterioration of soft vulcanized rubber, proceeding independently of actual wear, has always been a source of annoyance to the trade. Although evidences of such deterioration are varied in character, the many forms may be conveniently classified as surface deterioration and deterioration throughout the rubber. Surface deterioration, characterized by superficial film formation, is greatly accelerated when vulcanized rubber is exposed to light, particularly rays of short wave length, but that this function of light in the destruction of rubber is indirect in operation was recognized as early as 1883. by Burhardt (Jour. Soc. Chem. hid. 2, 119, 1883). The agency responsible for the changes which rubber undergoes on exposure to the atmosphere is undoubtedly oxygen, and suggested by Spiller (Jour. Chem. Soc. [London] 18, 44, 1865), as far back as 1865. That oxygen is essential for the deterioration of rubber has been shown by Fickenday (Kolloid Ztg. 9, 81, 1911), and many others since. The effect of sunlight on either raw or vulcanized rubber, is believed by Henri (Caout. et Gutta Percha 7, 2848, 1909) to be analogous, although Peachy and Leon (Jour. Soc. Chem. Ind. 37, 56T, 1918) offer the opinion that vulcanized rubber oxidizes less rapidly than raw rubber. Later investigators have proceeded still further in their conclusions, and Tuttle (The Rubber Age, N. Y. 8, 271-2, 1921) states, after studying the acetone solubility curves of vulcanized rubber exposed to light, that the action of the latter is one of oxidation, which when once started proceeds rapidly, due to the catalyzing effect of small amounts of oxidized rubber so formed.

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