Abstract
ABSTRACT Specialty natural rubber (SpNR) latex, namely, deproteinized natural rubber (DPNR) latex and epoxidized natural rubber (ENR) latex, has been produced to meet specific product's requirements. However, SpNR is normally used in the form of block rubber to manufacture dry rubber products such as tires and automotive parts. The applications of SpNR latex into latex foam products will be diversified. Findings indicate that foamability of SpNR latex is lower compared to normal latex (LATZ) but shows longer stability time after foamed. Findings also indicate that foam collapse and foam coagulate are two main challenges in the fabrication process of SpNR latex foam. Despite these challenges, SpNR latex foam can be fabricated at different density levels. During the foaming process, additional foaming agent is required to fabricate a SpNR latex foam, which is different from fabricating a normal NR latex foam, especially at low latex foam density. Consequently, a higher level of sodium silicofluoride, used as the gelling agent, is required to set the cell structure of the foam. Findings also indicate that foam density influenced the gelling time and volume shrinkage of the SpNR latex foam. An ideal compounding, foaming, and gelling formulation to fabricate SpNR latex foam via Dunlop batch foaming process has been developed. Morphological study showed that all latex foams are open-cell structure, with lower density foam exhibiting higher porosity and mean pore size. Comparison on hysteresis behavior between DPNR and ENR latex foam indicated that ENR latex foam exhibits higher hysteresis loss ratio compared to DPNR latex foam.
Highlights
IntroductionMicrocellular polymers which are known as polymer foams have received considerable attention among academia and industrial players due to their lower density and lighter weight, lower thermal conductivity, and higher load bearing strength per weight compared to normal non-cellular polymeric materials.[1,2,3,4] These properties are beneficial in numerous applications such as building & construction, packaging, furniture & bedding, footwear, sports & recreational, aeronautic and automotive industries.[5,6] the porous structure of polymer foam make them an excellent substitute for various functional materials that are used as barriers such as thermal and sound barriers, impact absorbers, and vibration dampers.[7]
The viscosity of prevulcanized Natural rubber (NR) latex could be correlated to the colloidal stability of the material, in which depends on many factors such as prevulcanization temperature and time, the amount and type of stabilizers and the dosage of vulcanizing ingredients, as well as the total solid content (TSC) and particle size of the latex itself
This study proved that, Specialty natural rubber (SpNR) latex concentrate can be used to produced latex foam
Summary
Microcellular polymers which are known as polymer foams have received considerable attention among academia and industrial players due to their lower density and lighter weight, lower thermal conductivity, and higher load bearing strength per weight compared to normal non-cellular polymeric materials.[1,2,3,4] These properties are beneficial in numerous applications such as building & construction, packaging, furniture & bedding, footwear, sports & recreational, aeronautic and automotive industries.[5,6] the porous structure of polymer foam make them an excellent substitute for various functional materials that are used as barriers such as thermal and sound barriers, impact absorbers, and vibration dampers.[7]. A possible solution is to substitute synthetic polymers with natural polymers. Substituting synthetic polymers with natural polymers is a great challenge. This is because most of the natural polymers are unable to comply with the foam product specifications and performances.[4,14,15]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
