Biodegradable Foams Research Articles

Characteristics of Biodegradable Foam (Bio-foam) Made from Cassava Flour and Corn Fiber

Plastic in the form of Styrofoam is a synthetic polymer material which is very practical in its use. This garbage is very damaging to the environment if it is burned because it produces gases that are dangerous to human respiration. The use of styrofoam must be stopped and do an alternative effort for any eco-friendly packaging materials, namely bio-foam which uses starch as the main raw material. The potential source of starch is tapioca flour, and the main source for fiber is corncob for several reasons including plastics made from starch/biomass which are more easily decomposed by nature and are abundant, also less utilized. This research was conducted with taking fiber from the corncob waste, then mixing it with tapioca, sorbitol, Mg stearate, and PVA. After obtaining the bio-foam, a water absorption test and biodegradability test were carried out. The results of the water absorption test showed that the 1st treatment had the greatest water absorption, exactly at the immersion time in the amount of 15 minutes in 25.45%, while the biodegradability test with soaking time in the soil for 14 days showed that 1st treatment was the most easily degraded by 20.25%.

Sunflower Oil Industry By-product as Natural Filler of Biocomposite Foams for Packaging Applications

The use of agroindustry by-products as reinforcements and/or composites filler is an innovative and economically attractive option that is still under study. Hence, the present work aims to study composite foams based on cassava-starch and sunflower oil press cake (SOPC), an oil industry by-product, using urea as an additive to enhance the biocomposites foaming capacity. Filler content (0, 20, and 40 wt%) and urea addition effect on foam morphology, physical properties and mechanical behaviour were analysed and compared to a benchmark polystyrene (PS) foam. In comparison with conventional PS foams, biofoams containing urea presented comparable mechanical properties yet higher hydrophilicity. Besides, formulations containing SOPC resulted in denser and harder materials and higher water uptake capacity than starch-based foams. Results provide further insights into biobased biodegradable foams development using agroindustrial residues as raw material and urea as foaming agent, with promising characteristics for food packaging.

CHARACTERIZATION OF PHYSICAL AND MECHANICAL PROPERTIES OF BIODEGRADABLE FOAM FROM MAIZENA FLOUR AND PAPER WASTE FOR SUSTAINABLE PACKAGING MATERIAL

Biodegradable Foam (Biofoam) production is an effort to reduce plastic waste in Indonesia. This product is made to replace Styrofoam, whose raw material is carcinogenic in the form of styrene which cannot be dissolved by the digestive system and is difficult to excrete through urine or feces which can trigger the growth of cancer in the long term and is harmful to the environment. Biofoam in this study is made from cornstarch with the addition of cellulose taken from paper waste. Based on the research that has been done, cornstarch-based biofoam with the addition of cellulose from paper waste as a biofiller can affect the physical and mechanical characteristics of the biofoam produced. The biofoam with a starch:cellulose ratio of 13:10 grams resulted in the best value of water adsorption in the amount 47.26%, also give the best result on tensile strength value and biodegradability value in the amount of 4.548 MPa and 11.943%. The addition of cellulose to the biofoam mixture in an appropriate amount will reduce the water absorption value of the biofoam. Because cellulose can cover the cavities generated by the starch expansion process in the biofoam. Therefore, the addition of cellulose also affects the mechanical properties of biofoam, namely tensile strength. Where the low filler composition in the biofoam will increase the tensile strength, but when the filler composition has passed an optimum point, the filler particles will experience agglomeration thereby reducing the tensile strength of the biofoam product. The variation in operating conditions in the manufacture of starch-based biofoam with the addition of a biofiller in the form of cellulose from paper waste did not significantly affect it. The variation in operating conditions only affects the visual appearance of the biofoam produced. Biofoam samples with the best visual appearance were produced at an operating temperature of 160 ? with an operating time of 30 minutes. Where high temperatures can affect th

Novel composite foam made from starch and water hyacinth with beeswax coating for food packaging applications

A novel composite foam was prepared from native cassava starch and water hyacinth (WH) by baking in a hot mold. The effects of WH powder content (0, 3, 5, 7 or 10 wt%, dry starch basis) on the properties of the starch foam were investigated. A starch foam formulation with 5 wt% WH powder exhibited the highest flexural stress at maximum load (3.42 MPa), the highest flexural strain (extension) at maximum load (3.52%), the highest modulus (232.00 MPa), the lowest moisture content (6.77%) and the most uniform cell size distribution (0.44 ± 0.09 mm). Moreover, mechanical properties of starch foam with 5 wt% WH powder were better than the same properties of some commercial foams. After being coated with beeswax, the starch foams retained their shape after immersion in distilled water and their water solubility was significantly reduced. Results indicated that a starch foam/5 wt% WH composite with beeswax coating was a biodegradable foam that could possibly replace commercial non-degradable foam.

Foamability and Special Applications of Microcellular Thermoplastic Polymers: A Review on Recent Advances and Future Direction

Back Cover: In article number 2000366, Suprakas Sinha Ray and Ritima Banerjee report a comprehensive and critical overview of state-of-the-art inthermoplastic polymeric foams, including significant developments, which can shape future research and industrial applications of these foams as sustainable engineering materials. Other highlights include studies on degradation kinetics of biodegradable foams, special morphology development for scaffolds, packaging, and acoustic applications, as well as cell seeding studies in scaffolds.

Foamability and Special Applications of Microcellular Thermoplastic Polymers: A Review on Recent Advances and Future Direction

AbstractFoaming of thermoplastics is an area of significant research interest. The substitution of any solid polymer with its foamed counterparts not only results in the lowering of material and fuel consumption but also enhances the scope of tailoring of properties for new applications. The key to manufacturing a useful foam is to achieve the desired morphology and volume expansion ratio as per the product requirements. In addition, other properties may become important, depending on the applications. Open‐cell structure, biocompatibility, biodegradability, and cytocompatibility are required in scaffolds. The ease with which a polymeric material can be foamed to achieve the desired properties depends on material characteristics, processing conditions, and the blowing agent. This article reviews key literature related to factors affecting foamability and ways of enhancing the foamability of various polymeric materials. Other highlights of this review include studies on degradation kinetics of biodegradable foams, special morphology development for scaffolds, packaging, and acoustic applications as well as cell seeding studies in scaffolds. In summary, this review is expected to provide direction for future developments in the field of microcellular processing to advance the technology and applications of thermoplastic foams as sustainable materials.

Advances in natural rubber seed shell utilization in polymer technology

The valorization of rubber seed shell into useful materials for industrial applications in polymer technology is of great interest. The usefulness of this material is borne out of the ease of processing; it’s readily available at low or no cost, and less abrasive to equipment. Literature and research reports have shown that rubber seed shell has gained applications in the adhesive industry as reinforcing additive, in electrode manufacturing, as filler in polymer composites, as sorbent in the uptake of heavy metals during waste water treatments, as starting material in the production carbon materials for value added products for the industry. However, there are still outstanding prospects in the utilization of this material in various areas of polymer technology such as a lignocellulosic source for the production of biodegradable foams, polymer gels, second generation bio-plastics and biofuels, and as surfactants. This review examines the results of a retrospective and prospective study in polymer technology of the latent properties inherent in rubber seed shell with particular emphasis on its utilization in polymer technology.

Increased expansion ratio, cell density, and compression strength of microcellular poly(lactic acid) foams via lignin graft poly(lactic acid) as a biobased nucleating agent

Green and renewable foaming poly(lactic acid) (PLA) represents one of the promising developments in PLA materials. This study is the first to use the lignin graft PLA copolymer (LG‐g‐PLA) to improve the foamability of PLA as a biobased nucleating agent. This agent was synthesized via ring‐opening polymerization of lignin and lactide. The effects of LG‐g‐PLA on cell nucleation induced by the crystallization, rheological behavior, and foamability of PLA were evaluated. Results indicated that LG‐g‐PLA can improve the crystallization rate and crystallinity of PLA, and play a significant nucleation role in the microcellular foam processing of PLA. LG‐g‐PLA improved the foam morphology of PLA, obtaining a reduced and uniform cell size as well as increased expansion ratio and cell density. With the addition of 3 wt% LG‐g‐PLA content, the PLA/LG‐g‐PLA foams increased the compressive strength 1.6 times than that of neat PLA foams. The improved foaming properties of PLA via a biobased nucleating agent show potential for the production and application of green biodegradable foams.

WITHDRAWN: Green Fabrication Method of Layered and Open-Cell Polylactide Foams for Oil-Sorption via Pre-Crystallization and Supercritical CO2-Induced Melting

Abstract This paper investigated the condensed state structure evolution of pre-crystallized polylactide (PLA) under supercritical CO2 (scCO2) and its influence on the foaming behavior of PLA. An interesting phenomenon was found, in which the pre-crystallized PLA can form a layered condensed state structure with a molten skin layer and a crystalline core at low temperatures under scCO2, and as the temperature increases, the width of the molten skin layer and the melting degree of the core gradually increases until a uniform non-layered molten state structure is formed. On this basis, layered and non-layered PLA foams were prepared at low and high temperatures, respectively. For the non-layered PLA foam, the skin layer and the core show similar closed or opened cell structure, where the open-cell PLA foams exhibit excellent oil-sorption properties. This paper provides a solvent-free idea for the green fabrication of bio-based and biodegradable oil-sorption foam.

Starch-Based Foam Packaging Developed from a By-Product of Potato Industrialization (Solanum tuberosum L.)

The use of petroleum-based packaging and its disposal in the environment poses several environmental problems, driving research into the development of biopolymers as substitutes for conventional polymers. Therefore, this study used the by-product of potato industrialization as the main raw material, xanthan gum as a plasticizer, and natural oat fiber as reinforcement to develop a biodegradable foam through thermo-pressing. The morphology, mechanical properties, and biodegradability of the final product were investigated. The water absorption and solubility index were highest in the sample with 20% plasticizer and 20% fiber. The water activity was not affected by variations in additives. The samples with the highest concentration of additives had the highest mechanical tensile strength, but there was a limit to these levels for foam resistance. The most accentuated visual effect was the yellow color. It is believed that hydrolysis was the main foam degradation mechanism, which took between 14 and 20 days for total decomposition. The combination of a by-product from potato industrialization with xanthan gum and natural oat fiber made it possible to produce a promising substitute for synthetic polymers, providing an environmentally friendly solution for both the use of agro-industrial by-products and reducing the volume of petroleum-based packaging waste.

Utilization of Solid Waste from Refined Sugar Industry (Filter Cake) as Biodegradable Foam (Biofoam)

Biodegradable foam (biofoam) is an environmentally friendly alternative packaging to replace Styrofoam. The aim of this research is to synthesize biofoam from blotong waste, obtain its characteristics and determine the economic feasibility of developing the produced biofoam product. This research was conducted with descriptive experimental methods and economic feasibility studies through NPV and PI calculations. The results of this study indicate that biofoam with the addition of a glycerol plasticizer of 15% w / w has the best characteristics, which contain water content (6.321%) and the lowest water absorption (17.181%) and tensile strength (6.7778 N / mm2) and elongity (174.5%) are higher when compared to styrofoam packaging. All biofoam can be completely degraded within 25-30 days. The addition of glycerol plasticizer generally affects the characteristics of the biofoam produced. Based on the results of the analysis of the economic feasibility study, the development of biofoam based blotong products is feasible (positive NPV; PI> 1).

Operative and environmental performance of a hot-foam machine for the herbicide-free weeding of the vineyard

The elimination of chemical herbicides use is a key factor in vineyards, particularly in the case of biological cultivation. The machines employed for mechanical weeding under the vine row are often characterised by low travelling speeds and therefore also by a low working capacity. A new solution is the application of hot foam, to transmit heat to weeds. A hot-foam machine for the herbicide-free weeding of vineyards was then developed, to produce and deposit foam directly onto weeds. The foam strips produced were approximately 40 cm width and 20-25 cm height, with a temperature exceeding 75°C. The future success of this environmentally sustainable technique will be the identification of a 100% naturally biodegradable and long-lasting foam, to maximize heat transmission to weeds.

Sustainable production and utilization of sago palm resource

Sago palm (Metroxylon sagu Rottb.) is distributed in Southeast Asia and Melanesia, and it produces comparatively high yield of starch (more than 200 kg per plant). This species can grow in wetland swamps where other food crops cannot grow economically and adapt to problem soils such as acid or saline with low input. The Society of Sago Palm Studies and the authors have published books entitled “The Sago Palm: The Food and Environmental Challenges of the 21st Century (Kyoto Univ. Press 2015)” and “Sago Palm: Multiple Contributions to Food Security and Sustainable Livelihoods (Springer 2018)”. This paper provides a brief review on (1) characteristics of seed germination and preparation of planting materials utilizing germinated seeds, (2) symbiosis of sago palm and microbes (nitrogen fixing bacteria or arbuscular mycorrhizal fungi), (3) creating new value from pith waste after conventional starch extraction (recovery of starch, ethanol production or preparation of biodegradable foam from the waste) and (4) utilization of leaf or bark from our former publications and the achievements published in our journal ‘SAGO PALM’ or the proceedings of the International Sago Symposium to discuss sustainable production and utilization of sago palm resource in Asia and Pacific.

Study of interactions between cassava starch and peanut skin on biodegradable foams

The present work reports the effects of adding an agro-industrial residue (peanut skin) to cassava starch-based foams developed by thermopressing process. For this purpose, foams composed of cassava starch (CS foams) and cassava starch added of 24% (w/w) of peanut skin (CS/PS foams) were compared regarding their chemical structures, thermal, morphological and mechanical properties, moisture sorption isotherms, contact angle, and biodegradation. Results of dynamic mechanical analysis (DMA) showed the addition of peanut skin reduced the stiffness due to the increase of mobility of the starch chains. CS/PS foams exhibited a decrease in the storage modulus and glass transition temperatures as observed DMA. The addition of peanut skin did not influence on tensile stress and Young’s modulus but reduced the tensile strain of the foams. The water contact angle of CS/PS foam was higher than CS foam, and as a result, CS/PS foams were found less hydrophilic than CS foams, which broaden the application of these materials. The reduction of hydrophilicity was related to the composition of the additive, mainly regarding lipids and proteins fractions, as well as to the interactions between cassava starch and peanut skin, reducing the availability of OH groups to bond with water.

Saponin foam for soil remediation: On the use of polymer or solid particles to enhance foam resistance against oil

Foams can be used to remediate aquifer pollution due to industrial leaks. However, when in contact with oily pollutants, foams may collapse and thus have a very limited life-time. A suitable formulation of biodegradable foam that resists oil contact is therefore needed. Hence, the ability of xanthan polymer and silica colloidal particles to stabilise foam against oil was investigated. Their performance in terms of stabilisation was evaluated via foam generation experiments in columns of porous medium, conducted with and without oil. The results show that the addition of xanthan polymer led to an increase in the viscosity of the solution, which thwarted the formation of foam. It did not improve the resistance of foam to oil, but increased altogether the resistance factor up to more than twice the original value. Concerning silica particles, it was demonstrated that they both noticeably increased resistance factor and moderately stabilised foam against oil by 20% at optimum concentration. As such, this study presents a new way to reinforce foam against oil for soil remediation issues.

Cellulose Nanostructure-Based Biodegradable Nanocomposite Foams: A Brief Overview on the Recent Advancements and Perspectives.

The interest in designing new environmentally friendly materials has led to the development of biodegradable foams as a potential substitute to most currently used fossil fuel–derived polymer foams. Despite the possibility of developing biodegradable and environmentally friendly polymer foams, the challenge of foaming biopolymers still persists as they have very low melt strength and viscosity as well as low crystallisation kinetics. Studies have shown that the incorporation of cellulose nanostructure (CN) particles into biopolymers can enhance the foamability of these materials. In addition, the final properties and performance of the foamed products can be improved with the addition of these nanoparticles. They not only aid in foamability but also act as nucleating agents by controlling the morphological properties of the foamed material. Here, we provide a critical and accessible overview of the influence of CN particles on the properties of biodegradable foams; in particular, their rheological, thermal, mechanical, and flammability and thermal insulating properties and biodegradability.

Pineapple shell fiber as reinforcement in cassava starch foam trays

Pineapple shell, considered a waste in the juice industry, was used as a reinforcement material to produce biodegradable foam trays (FTs) based on cassava starch by a compression molding process. These foams were prepared with different starch/fiber ratios and then were characterized according to their microstructure and physical and mechanical properties. The starch/fiber ratio of 95/5 showed the lowest values of thickness and density (2.58 mm and 367 kg m−3, respectively). There was a good distribution of the pineapple shell fiber throughout the polymeric matrix. All FTs showed a semicrystalline structure and 95/5 ratio showed the highest crystallinity index (CI) value (39%). In addition, this ratio improved the tensile strength of the FTs, obtaining similar values to expanded polystyrene (EPS) samples, used as the reference material. Nevertheless, all FTs reinforced with pineapple shell fiber showed high water absorption capacity (WAC); therefore, future studies should focus on to improve the physicochemical and structural properties of the cassava starch-based foams, considering the promising potential of this novel biodegradable material for dry food packaging, such as a viable alternative to reduce the use of petroleum-based materials such as commercial EPS trays.

Biodegradable and resilient poly (propylene carbonate) based foam from high pressure CO2 foaming

Poly(propylene carbonate) (PPC) is a biodegradable polymer incorporating over 40 wt% CO2 in the main chain. High-foaming ratio while resilient biodegradable PPC foam is quite difficult to prepare since PPC is a brittle aliphatic polycarbonate, and blending with other biodegradable plastics like poly(butylene adipate-co-terephthalate) (PBAT) faces the challenge of compatibility. Here, Joncryl ADR-4368 chain extender was successfully used as compatibilizer between PPC and PBAT. Even 1 wt% ADR-4368 in PPC/PBAT blend (29/70 in weight ratio) showed remarkable effect, where the tensile strength of the resulting blend showed Ca. 100% increase from 14.2 MPa to 28.9 MPa with the elongation at break increased from 491% to 1026%. Meanwhile, the complex viscosity at 150 °C and angular frequency of 10−1 rad/s increased 4.1 times from 308 Pa s to 1273 Pa s. As a bonus of PPC which is a CO2-philic polymer capable of absorbing 23.1 wt% CO2, uniform and resilient biodegradable foam was prepared under high CO2 pressure foaming, whose cell size was Ca. 15 μm with foam density of 0.083 g/cm3. It should be noted that the foam ratio increased from 3 to 15 with only 1 wt% ADR-4368 added.

Development of biodegradable semiconducting foam based on micro-fibrillated cellulose/Cu-NPs.

In this work regenerated cellulose was prepared by phosphoric acid as a primarily step in preparation of biodegradable foam. Copper nanoparticles (Cu-NPs) were embedded onto the cellulosic suspensions followed by freeze drying process. The scanning electron microscopy (SEM) revealed the presence of individual chunky regenerated cellulose fibers in the dimensions of micro that enhanced tendency to aggregate during drying. X-ray diffraction (XRD) demonstrated that, the treatment of cellulose with concentrated phosphoric acid led to defibrated cellulose with lower crystallinity index than original cellulose fibers. The study provided insights about the influence of the Cu-NPs on the structure, thermal stability and the electrical contributions of the considered cellulose-based foam. The electrical and dielectric properties were studied by means of the broadband dielectric spectroscopy. The dielectric spectra were dominated by an anomalous behavior of the permittivity as illustrated versus frequency of the investigated samples. The real part of conductivity follows the universal power law at higher frequencies. The foam loaded Cu-NPs exhibit biodegradability and highly efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans.

Biodegradable Foam Cushions as Ecofriendly Packaging Materials

In this work, a high-magnification extrusion-foaming technique for biomass-based biodegradable composite materials using water vaporization was examined. Starch was selected as the biomass and polylactic acid was selected as a biodegradable matrix resin. No additional plasticizer or additives were used in this extrusion-foaming process. The foaming ratio was deduced according to the conditions of the extrusion-foaming process to confirm the forming characteristics of the foaming materials. Scanning electron microscopy was performed to examine the morphology of the composite foam. To investigate the potential of the foam cushion as an ecofriendly packing material, we conducted experiments on its static compression and dynamic cushioning properties and examined whether its biodegradability could be controlled by varying the mixing ratio of the materials. Thus, we developed a water-foaming process that is ecofriendly and whose products can be recycled as compost after use.