Organic solvent-free hydrogenation of natural rubber latex and synthetic polyisoprene emulsion catalyzed by water-soluble rhodium complexes

Water-Soluble Substance: Characteristics and Effects on the Properties of Natural Rubber Latex

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.668.57 ◽

2013 ◽

Vol 668 ◽

pp. 57-64

Author(s):

Long Fei Fan ◽

Shuang Quan Liao ◽

Chao Qun Li ◽

Xiao Xue Liao ◽

Ming Wan Guo

Keyword(s):

Natural Rubber ◽

Natural Rubber Latex ◽

Degradation Process ◽

Water Soluble ◽

Soluble Substance ◽

Rubber Latex ◽

Small Molecular Weight ◽

Degradation Temperature ◽

Water Soluble Substance ◽

Main Component

Water-soluble substance is an important part of non-rubber substance in natural rubber latex and it has significant influence on the properties of natural rubber. The aim of this paper is mainly to study the composition of small-molecular-weight water-soluble substance (s-WSS) and its effects on the properties of natural rubber films. The analysis of IR and HPLC-MS showed that s-WSS (not including sugar) is composed of C3H4N4O6, C7H14O6, C11H13N3O5, C11H20O7 and C6H22N8. While the main component of s-WSS is C7H14O6 whichis a kind of alcohol. The tensile strength of the prepared composites can be increased at low loading of s-WSS. The tear strength of the prepared composites can be improved by adding s-WSS into natural rubber. The thermal oxidation degradation process of the samples has two stages. Compared with neat natural rubber latex, the initial degradation temperature was decreased significantly in both stages when s-WSS was added. While the degradation temperature range became larger in both stages.

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Surface Modification of Natural Rubber Latex Film Using Photocrosslinkable Chitosan

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.824 ◽

2012 ◽

Vol 482-484 ◽

pp. 824-829

Author(s):

He Ping Yu ◽

Zong Qiang Zeng ◽

Hong Chao Liu ◽

Yong Yue Luo

Keyword(s):

Contact Angle ◽

Natural Rubber ◽

Water Contact Angle ◽

Irradiation Time ◽

Natural Rubber Latex ◽

Water Soluble ◽

Latex Film ◽

Latex Films ◽

Rubber Latex ◽

Water Contact

Surface modifications of natural rubber latex films were carried out to improve the hydrophilicity by UV-induced immobilization of water-soluble butyryl derivative of chitosan using the photosensitive hetero-bifunctional crosslinking reagent, 4-azidobenzoic acid. The effects of the concentration of modified chitosan solution and UV irradiation time on the water contact angle values of natural rubber latex films were studied. ATR-FTIR analyses confirmed that the O-butylrylchitosan molecules were covalently bonded onto the surface of natural rubber latex film. The water contact angle value of natural rubber latex film which is about 95o reduces to 55o significantly with the introduction of O-butylrylchitosan. The results indicate that the hydrophilic behaviour of natural rubber latex film has been improved by immobilization of O-butylrylchitosan.

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Natural Rubber Latex and Gum Arabic: A Comparison of Physico-chemical Properties

10.20944/preprints202005.0291.v1 ◽

2020 ◽

Author(s):

Lawrence Edomwonyi-Otu

Keyword(s):

Natural Rubber ◽

Moisture Absorption ◽

Natural Rubber Latex ◽

Chemical Properties ◽

Shear Thickening ◽

Gum Arabic ◽

Absorption Capacity ◽

Water Soluble ◽

Rubber Latex ◽

Physico Chemical

The present investigation deals with the determination of the physio-chemical properties of two commercial grade samples of local gums (Gum Arabic and Natural Rubber Latex (NRL)). The results revealed that the gum samples have high melting point that indicate thermal stability at room and moderate temperatures. The gum samples have about 95 % carbohydrate content and a corresponding high internal energy and can serve as a source of energy. The rheology of the samples revealed shear-thickening characteristics with gum Arabic being thixotropic and pseudo-plastic in nature while NRL was observed to be anti-thixotropic and rheopectic. Further results from the moisture absorption, contact angle and Fourier Transform Infrared Radioscopy (FTIR) analyses gave better insight into their hydroscopic behaviors. Gum Arabic has excellent water absorption capacity with less wettability as it consists mainly of more water-soluble compounds in comparison to Natural Rubber Latex. These insights from the study will enhance wider application of the gums with increased value-addition to the gums and the communities where they (can) thrive.

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More Values of L-Quebrachitol from Skim Natural Rubber Latex

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.659.458 ◽

2015 ◽

Vol 659 ◽

pp. 458-462 ◽

Cited By ~ 1

Author(s):

Teerawan Wannuch ◽

Adun Nimpaiboon ◽

Jitladda Sakdapipanich

Keyword(s):

Antibacterial Activity ◽

Natural Rubber ◽

Colloidal Suspension ◽

Rubber Tree ◽

Natural Rubber Latex ◽

Water Soluble ◽

Low Grade ◽

Rubber Content ◽

Rubber Latex ◽

Bioactive Materials

Natural rubber (NR) latex collected from Hevea brasiliensis rubber tree exists as a colloidal suspension with 30% dry rubber content (DRC). For convenient use and transportation, the latex is concentrated by centrifugation process. Through this process, the 60% DRC concentrated NR latex and 5% DRC skim latex as a by-product were produced. After using acid coagulation of skim latex, the skim rubber is obtained to use as a low-grade application due to high amount of non-rubber components as impurities. The water portion remaining after the coagulation of skim rubber consists of various water-soluble materials such as sugars, lipids, proteins and minerals, which can cause the water pollution if serum is directly discharged into the environment without proper treatment. However, 1.5% of L-quebrachitol was found in skim latex. It can be used in many applications such as a starting material for the synthesis of bioactive materials and inositol pharmacy. Thus, this work is an attempt to investigate the most effective extraction method of L-quebrachitol from skim latex. It was found that the appropriate solvent for extraction L-quebrachitol at high temperature and for recrystallization at low temperature is ethanol. The yield of L-quebrachitol about 2-3% by weight of solid serum was obtained. Moreover, a sweetness and antibacterial activity were also studied for its further applications. It was found that the sweetness of L-quebrachitol was twice than that of sucrose. No antibacterial activity of L-quebrachitol against Staphylococcus aureus and Streptococcus mutans was found.

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