Tea Grounds as a Waste Biofiller for Natural Rubber

Area of Science:

• Materials Science
• Polymer Chemistry
• Sustainable Materials

Background:

• Natural rubber (NR) composites are widely used, but filler dispersion and aging resistance are key challenges.
• Ground tea waste (GT) is an abundant, low-cost byproduct with potential as a biofiller.
• Ionic liquids (ILs) are explored for their ability to modify filler-matrix interactions.

Purpose of the Study:

• To investigate the use of ground tea waste (GT) as a biofiller in natural rubber (NR) composites.
• To evaluate the effect of ionic liquids (ILs) on GT dispersion and NR composite properties.
• To assess the impact of GT loading and ILs on curing, mechanical, thermal, and aging characteristics.

Main Methods:

• Preparation of NR composites with varying GT loadings.
• Treatment of GT with specific ionic liquids (1-ethyl-3-methylimidazolium lactate and 1-benzyl-3-methylimidazolium chloride).
• Characterization of composites including curing, crosslink density, tensile properties, thermal stability, and thermo-oxidative aging resistance.

Main Results:

• Optimal GT loading (10 phr) significantly improved NR tensile strength by 40%; higher loadings led to agglomeration and reduced strength.
• Ionic liquids enhanced GT particle dispersion and increased crosslink density by 20% compared to unfilled NR.
• GT incorporation slightly reduced thermal stability but significantly improved thermo-oxidative aging resistance (aging factor increased by 25%).

Conclusions:

• Ground tea waste can be effectively utilized as a biofiller in natural rubber composites.
• Ionic liquids play a crucial role in improving filler dispersion and enhancing the overall performance of NR composites.
• GT-filled NR composites demonstrate improved mechanical properties and superior resistance to thermo-oxidative degradation, offering a sustainable alternative.