Development of Biodegradable Rigid Foams from Pineapple Field Waste

Abstract

Pineapple materials sourced from agricultural waste have been employed to process novel bio-degradable rigid composite foams. The matrix for the foam consisted of starch extracted from pineapple stem, known for its high amylose content, while the filler comprised non-fibrous cellulosic materials sourced from pineapple leaf. In contrast to traditional methods that involve preparing a batter, this study adopted a unique approach where the starch gel containing glycerol were first formed using a household microwave oven, followed by blending the filler into the gel using a two-roll mill. The resulting mixture was then foamed at 160 °C using a compression molding machine. The foams displayed densities ranging from 0.43–0.51 g/cm3 and exhibited a highly amorphous structure. Notably, the foams demonstrated an equilibrium moisture content of approximately 8–10% and the ability to absorb 150–200% of their own weight without disintegration. Flexural strengths ranged from 1.5–4.5 MPa, varying with the filler and glycerol contents. Biodegradability tests using a soil burial method revealed complete disintegration of the foam into particles measuring 1 mm or smaller within 15 days. Moreover, to showcase practical applications, an environmentally friendly single-use foam tray was fabricated. This novel method, involving gel formation followed by filler blending, sets it apart from previous works. The findings highlight the potential of pineapple waste materials for producing sustainable bio-degradable foams with desirable properties and contribute to the field of sustainable materials.

Development of Biodegradable Thermosetting Plastic Using Dialdehyde Pineapple Stem Starch

“…Notably, a discernible decline in diffraction intensity ensued post-glycerol plasticization. This divergence stands in contrast to PSS films created through solution casting methods [ 34 , 35 ]. Additionally, an emerging peak around 18.6° is observed, likely linked to the V-type crystalline structure.…”

“…The water resistance of the starch-based materials was conducted in terms of the water absorption and solubility by following the procedure reported by Namphonsane et al [ 35 ].…”

“…Moreover, films derived from PSS exhibit robust mechanical strength and exceptional water resistance, while retaining biodegradability [ 32 ]. The versatility of PSS-based materials has been explored in the creation of composite sheets [ 33 ], protective coatings for fruits and vegetables [ 34 ], rigid foam [ 35 ], water-based adhesives [ 36 ], food applications [ 37 , 38 ], and more. This renders PSS-based plastics appealing and presents an emerging challenge for their diverse applications.…”

New Composites Derived from the Natural Fiber Polymers of Discarded Date Palm Surface and Pineapple Leaf Fibers for Thermal Insulation and Sound Absorption

“…The sound absorption coefficient was found above 0.5 for most of the bound and hybrid composites. New bio-degradable composite foams made of pineapple stem starch and pineapple leaves were reported by Namphonsane et al [23]. Their results indicated that the flexural strengths of the composite foams ranged from 1.5 to 4.5 MPa.…”