Facile Strategy to Construct Metal–Organic Coordination Thermoplastic Starch with High Hydrophobicity, Glass-Transition Temperature, and Improved Shape Recovery

Abstract

In this work, a new type of metal–organic coordination polymer (MOP) was developed with thermoplastic starch (TPS) by reactive extrusion with zinc acetate (ZA). The resulting material, denoted as TPS-ZA, showed interfacial and mechanical improvements compared with crude TPS, including low wettability, good shape memory, high heat resistance, and high strength. The high hydrophobicity of TPS-ZA is surprising considering that ZA added in the TPS is highly soluble in water. Morphology characterizations revealed that the improvements were related to the micro/nanohierarchical architectures induced by coordination-driven self-assembly. Marked improvement in glass-transition temperature (from 48 to 89 °C) and transition from hydrophilicity to hydrophobicity (water contact angle from 56 to 118°) are noted for TPS-ZA with a ZA content of only 3−5 wt %. Meanwhile, the novel cluster aggregates serving as netpoints endow TPS-ZA with significant improvement in shape memory, with nearly 180° recovery angle and 99% shape fixity. We hence showcase reactive extrusion here as a facile strategy to prepare MOP with properties more suitable for daily applications. The prepared TPS-ZA may serve as a multifunctional disposable plastic to replace petroleum-based plastic material and remedy the pollution of “microplastics”.

Adopting Intrinsic Hydrophilic Thermoplastic Starch Composites to Fabricate Antifogging Sustainable Films with High Antibiosis and Transparency

“…The decrease in WCA due to the chemical state changes in TPS-BA3 with its intrinsic hydrophilic feature and improved surface energy (γ, Table S2) makes it exhibit outstanding antifogging performance without the need for constructing any superhydrophilic surface whose WCA should be lower than 10°. For example, we prepared a hydrophobic thermoplastic starch by metal–organic coordination with a WCA of 118°, while in this study, TPS-BA3 had an intrinsic hydrophilic matrix displaying an improved water-absorbing capability with the incorporation of BA, which is helpful to construct a flat water film (Figure b5,b6) and obtain a lower RI (Figure S4) to reduce the light scattering.…”

Facile Preparation of Eco-Friendly, Flexible Starch-Based Materials with Ionic Conductivity and Strain-Responsiveness

“…Recently, we and other researchers have found that some salt ions (e.g., Zn 2+ and Ca 2+ ) can not only disorganize and amorphize starch granules effectively but also reinforce the starch chain network by forming amylose–metal cation inclusion complexes. − Because these salt ions are hygroscopic and can combine with water to form hydrates easily, polymer materials containing them could have improved water-holding capacity . Moreover, these salt ions can impart the materials with electrical conductivity.…”

Biodegradable-Renewable Vitrimer Fabrication by Epoxidized Natural Rubber and Oxidized Starch with Robust Ductility and Elastic Recovery

“…Consequently, a functionalizing and sustainable filler that can be easily separated from the vitrimer matrix via a facile, mild, and green approach is required urgently. Starch (ST), an inexpensive natural polymer that is biodegradable, edible, and readily available, 40 can be a potential filler to fabricate ENR vitrimer. Strikingly, the amylolytic enzymes, such as α-amylase, can hydrolyze starch for the soluble production of dextrins and eventually glucose.…”

“…Starch (ST), an inexpensive natural polymer that is biodegradable, edible, and readily available, can be a potential filler to fabricate ENR vitrimer. Strikingly, the amylolytic enzymes, such as α-amylase, can hydrolyze starch for the soluble production of dextrins and eventually glucose. , Consequently, if ENR/ST vitrimer with high mechanical properties and shape memory can be fabricated, this sustainable polymer is expected to recycle ENR without filler content as ST can be hydrolyzed and separated.…”