Preparation, characterization and properties of liquid natural rubber with low non-rubber content via photodegradation

2020 ◽  
Author(s):  
Suhawati Ibrahim ◽  
Nadras Othman ◽  
Nurul Hayati Yusof
Keyword(s):  
Natural Rubber ◽  
Rubber Content ◽  
Liquid Natural Rubber

Studies on reinforcing effect of industrial nano silica in chloroprene vulcanizates containing carboxy-terminated liquid natural rubber

2021 ◽  
pp. 009524432110635
Author(s):  
Gopika Sudhakaran ◽  
Shanti A Avirah
Keyword(s):  
Maleic Anhydride ◽  
Natural Rubber ◽  
Cost Effective ◽  
Cross Linking ◽  
Nano Silica ◽  
Rubber Content ◽  
Reinforcing Effect ◽  
Bound Rubber ◽  
Liquid Natural Rubber ◽  
Rubber Filler

Maleic anhydride was chemically attached to depolymerized natural rubber, and the product was named as carboxy-terminated liquid natural rubber (CTNR). The CTNR can act as a potential plasticizer in chloroprene (CR) vulcanizates. This paper describes the use of commercial nano silica (NS) as a promising cost-effective filler, which can enhance the tensile properties and ageing resistance of the CR vulcanizates incorporated with CTNR (CR-CTNR). The enhancement in properties may be attributed to the increased bound-rubber content owing to the large surface area of the nano-sized filler. The characteristics of the NS-filled CR vulcanizates containing CTNR (NS CR-CTNR) were compared with those containing amorphous silica. The NS CR-CTNR vulcanizates showed superior ageing and oil resistance due to the finer rubber filler interaction modified by ionic cross linking.

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

Chemical Depolymerisation of Natural Rubber in Biphasic Medium

2014 ◽  
Vol 1024 ◽  
pp. 193-196
Author(s):  
Ibrahim Suhawati ◽  
Asrul Mustafa
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Chemical Structure ◽  
Inner Core ◽  
Particle Surface ◽  
Natural Rubber Latex ◽  
Carbonyl Groups ◽  
Latex Particles ◽  
Liquid Natural Rubber ◽  
Biphasic Medium

The molecular weight of natural rubber (NR) can be reduced via depolymerization reaction to produce liquid natural rubber (LNR) with a molecular weight less than 50 000 g/mol. In the reaction, hydrogen peroxide and sodium nitrite were added to natural rubber latex to initiate a redox type reaction which then breaks the NR chain. Low permeation of reagents into latex particles allows the degradation to occur greater at the latex particle surface relative to the inner core contributes to high molecular weight distribution (MWD) or polydispersity of the LNR obtained. In this recent works, the reaction was carried out in a biphasic medium consisting of water and toluene phases. Toluene swells latex particles as indicated by the SEM micrographs showing changes in the size of latex particles. This occurrence is suggested to increase the influx of reagents into the latex particles. Consequently, with higher permeation of reagents into the latex particles resulted in the decrease of molecular weight and lower polydispersity of the LNR obtained. Chemical structure analysize showed that the LNRs obtained were attached with hydroxyl and carbonyl groups.

Thermal Properties and Crystallisation Behaviour of Thermoplastic Natural Rubber (TPNR) Nanocomposites

2013 ◽  
Vol 812 ◽  
pp. 125-130 ◽  
Author(s):  
Siti Norasmah Surip ◽  
Z.Y. Zhang ◽  
H.N. Dhakal ◽  
N.N. Bonnia ◽  
S. H. Ahmad
Keyword(s):  
Thermal Properties ◽  
Natural Rubber ◽  
Nucleating Agent ◽  
Preparation Technique ◽  
Preparation Methods ◽  
Blending Method ◽  
Liquid Natural Rubber ◽  
Tan Δ ◽  
Thermoplastic Natural Rubber ◽  
Internal Mixer

The effect of preparation technique on the crystallisation behavior and thermal properties of TPNR filled nanoclay nanocomposites was investigated. The nanocomposites were prepared via melt blending method using internal mixer (Haake 600P). Two types of nanocomposites preparation technique were employed which is method A and B. In method A, the nanoclay was pre-mixed with liquid natural rubber (LNR) before it was charged into the other materials. For method B, the nanoclay was directly charged into the molten TPNR matrix. The result shows, preparation methods were significantly affect the crystallinity and thermal properties of TPNR nanocomposites. DSC thermogram revealed that nanocomposites crystallinity was increased when prepared by method A but decreased with method B. An increment in polypropylene crystallinity was attributed by the nanoclay which is believed to be as a nucleating agent. DMA thermogram suggested that the preparation method has affected the storage modulus and tan δ but not the glass transition temperature (tg).

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.

Inorganic-Organic Composite Materials from Liquid Natural Rubber and Epoxidised Natural Rubber Derivatives

2017 ◽  
pp. 128-140
Author(s):  
Wan Ahmad Kamil Mahmood ◽  
Mohammad Hossein Azarian
Keyword(s):  
Composite Materials ◽  
Natural Rubber ◽  
Sol Gel ◽  
Polymeric Materials ◽  
Metal Alkoxides ◽  
Inorganic Glass ◽  
Transparent Films ◽  
Polymer Component ◽  
Liquid Natural Rubber ◽  
Preparation Techniques

Organic-Inorganic composite materials (OICs) are used to describe the group of materials synthesized from polymers and inorganic metal alkkoxides. The interests in these materials arised from the need to ‘combine' the physical properties of inorganic glass materials and polymers such that the resultant OICs have the strength of the inorganic glass and flexibiliy of polymeric materials. Sol-gel technique have been the technique of choice due to much of its advantages, in particular the low temperature reaction. This is very important when natural rubber and its derivatives are used as the polymer component of the OICs. Work in our laboratory has demonstrated that OICs form liquid natural rubber (LNR) and 50% epoxidised natural rubber (ENR-50) can be prepared from various metal alkoxides, such silicon, zirconium and titanium. The OICs can be prepared as flexible transparent films, nanofibers and nanobeads. This Chapter will describe the preparation techniques and the properties of these OICs from various compositions of one and more metal alkoxides in both LNR and ENR-50. The applications of these materials in PANI will be briefly described.

Sign in / Sign up

Export Citation Format

Share Document