Eco-friendly natural rubber latex and modified starch-based adhesive for wood-based panels application- A review

The use of formaldehyde-based synthetic adhesives for the development of wood-based panels has increased rapidly in the industry. Synthetic adhesives are regarded as a threat to human health and a pollutant because they emit formaldehyde's carcinogenic gas. The breakthrough has prompted to seek for a long-term solution to the formaldehyde threat with natural resources. There has been a significant rise in bio-based adhesive technology and development in the wood-based panel industry. The current review article is intended to present the potentials and the drawbacks of the development of bio-adhesives from sustainable resources such as natural rubber latex (NRL) and starch. This review also discussed the chemical modification and crosslinkers of starch to improve water resistance and adhesion properties. Moreover, this article discusses the compatibility of modified rice starch and NRL for their conclusive applications as wood-based panels adhesive. The findings suggested that bio-based adhesives could replace more synthetic-based adhesives with comparable performance in the near future.

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Effects of Drying Temperature on the Properties of Deproteinized Natural Rubber Latex/Starch Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.747.99 ◽

2013 ◽

Vol 747 ◽

pp. 99-102 ◽

Cited By ~ 1

Author(s):

Rungtiwa Waiprib ◽

Prapaporn Boonme ◽

Wiwat Pichayakorn

Keyword(s):

Natural Rubber ◽

Testing Machine ◽

Composite Films ◽

Natural Rubber Latex ◽

Physical And Mechanical Properties ◽

Rice Starch ◽

Surface Films ◽

Rubber Latex ◽

Drying Temperature ◽

Deproteinized Natural Rubber

The aim of this study was to observe the effects of drying temperature on the properties of deproteinized natural rubber latex (DNRL)/starch composite films. These composite films were prepared by simple mixing and then drying at different temperatures of 50, 60 and 70°C. Various parameters such as types (potato, sago, bean, corn, tapioca, rice, and glutinous starches), amounts (5-20 part per hundred of rubber (phr)) and water-dispersed concentrations (5-50%) of starch blended were evaluated. It was found that only some DNRL/starch composite formulations could be prepared as the completely homogeneous films. Drying temperature affected the degree of starch gelatinization that confirmed by differential scanning calorimeter (DSC) technique. The DNRL composite films of 20 phr of all 7 starch types could be formed at 50 and 60°C, while those of 20 phr sago, bean, corn, and rice starch could be formed at 70°C. Some of these films were difficult to be the completely dry films at 70°C due to their more degree of gelatinization of starch on the surface films which inhibited the evaporation of water inside the films. However, only some DNRL/starch composites showed the homogeneous film under cross-section scanning electron microscopy (SEM) observations. Their compatibilities were confirmed by Fourier transform infrared spectroscopy (FT-IR) and DSC. Their physical and mechanical properties were further evaluated by the universal testing machine.

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Efficient stoneware hand mold for slip casting in natural rubber latex glove preparation

Progress in Rubber Plastics and Recycling Technology ◽

10.1177/1477760619895013 ◽

2020 ◽

Vol 36 (4) ◽

pp. 262-283

Author(s):

Nuchnapa Tangboriboon ◽

Sukritchai Teeraroengrit ◽

Pattara Chawhuaymhak ◽

Jirarat Kamonsawas ◽

Sairung Changkhamchom ◽

...

Keyword(s):

Natural Rubber ◽

Slip Casting ◽

Natural Rubber Latex ◽

Maximum Load ◽

Mold Surface ◽

Rubber Latex ◽

Adhesion Properties ◽

Elongation At Break ◽

Latex Glove ◽

Pharmaceutical Industries

Disposal medical gloves are an important product to maintain hygienic conditions, ensuring security for patients and safeguarding against infections. They are used in many fields, such as dental and medical, beauty and cuisine, food and pharmaceutical industries. Presently, aging populations and an emerging middle class in developing countries require medical gloves at a higher volume. Therefore, the demand for medical gloves increases continuously. In this work, two types of hand molds were prepared from stoneware clay and plaster to be used in the natural rubber glove preparation. The ceramic stoneware and plaster hand molds were prepared by the slip casting. The obtained stoneware hand molds were found to be superior to the commercial hand molds. Natural rubber latex (NRL) gloves were fabricated by dipping the stoneware hand mold coated with a coagulant into the NRL compound using the sulfur curing system at 120°C for 30 min. The latex solid:water weight ratio, drying and firing temperatures, and firing time used to prepare stoneware hand molds were found to affect the adsorption–adhesion properties between the mold surface and the NRL films. The obtained NRL films were further characterized for the physical properties such as appearance, film thickness, tackiness, and effusion of the phase formation by X-ray diffraction, the microstructure by scanning electron microscope, and the mechanical properties. The NRL glove films prepared by the stoneware hand mold possessed the high percentage elongation at break and the maximum load stress equal to 1343.30 ± 78.36% and 12.74 ± 2.34 MPa, respectively. On the other hand, the latex glove films prepared by the plaster hand mold with 80 consistency provided the percentage of elongation at break and the maximum load stress equal to 531.76 ± 2.54 and 21.01 ± 0.08 MPa, respectively.

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