Biodegradable Foams Research Articles

A novel “reinforcing-foaming-recovering” strategy for achieving thermally insulating green foams with ultrafast degradation

Lightweight porous materials have garnered increasing attention in application domains of intelligent construction and flexible thermal insulation, owing to their customizable 3D porous structures and outstanding performances. Nonetheless, the severe environmental pollution resulting from the accumulation of non-degradable plastic waste in the ecosystem has sparked significant interest in developing bio-degradable thermal insulation foams. The preparation of biodegradable foam, however, typically requires operating specialized equipment for long periods under extreme conditions, which diminishes its environmental friendliness as claimed. Herein, we present a pioneering "Reinforcing-Foaming-Recovering" strategy to achieve ultralight and recyclable green foams with excellent thermal insulation properties. This innovative strategy, involving materials reinforcing and low-pressure foaming complemented by nitrogen-assisted gas recovering enables the preparation of low-density (0.08 g/cm3) biodegradable foams with restricted shrinkage ratio (<5%). Thanks to the easy-to-control foaming method, combined with the improved 3D network cellular structures caused by nitrogen-assisted gas exchange, the achieved green foams exhibit favorable thermal insulation (39.8 mW/m·K) and superior biodegradation efficiency (11.5%/2 months). The approach of energy-efficient nitrogen-assisted low-pressure foaming of degradable polymers offers a promising and practical solution for producing eco-friendly and multifunctional porous materials with economic advantages.

Synthesis And Characterization of Biodegradable Foam (Biofoam) From Taro Starch (Colocasia Aesculenta)-Chitosan

Biodegradable foam can be used as an alternative packaging which is safe for health and environment. The raw material used to produce biofoam is starch. Taro consist of 67.42% starch. Contrarily, biofoam produced from starch has fragile mechanical properties. The addition of chitosan aims to improve the mechanical properties of biodegradable foam. Beside that, Chitosan is expected to reduce water absorption and increase tensile strength of biodegradable foam without reducing degradability. Biodegradable foam was synthesized by three steps, first step was isolation of starch from taro, second step was synthesis of biodegradable foam from taro starch-chitosan which used various concentration of chitosan to study the effect of chitosan addition for mechanical properties of biodegradable foam. Various concentration of chitosan was 0%, 1%, 2%, 3%, and 4% (w/w). Third step was characterization of biodegradable foam. The Analysis of biodegradable foam was carried out included FTIR functional group, mechanical properties, biodegradability and water absorption. The result showed that the best tensile strength test was 1% chitosan addition with a value of 3.75 MPa; based on water absorption test, the optimum sample was 4% chitosan addition with a value of 11.66%. The results of the functional group analysis of FTIR biodegradable foam contained of C=O (amide), CN, NH and OH groups which indicated the existence of chitosan in the sample.

Synthesis Of Biofoam Based On Glucomannan Porang And Polyvinyl Alcohol (PVA) With The Addition of Seaweed Dregs

Biofoam (Biodegradable foam) is an alternative packaging to Styrofoam made from natural raw materials that can be biodegraded in the soil. Biofoam is generally made from 3 constituent materials in the form of main ingredients in the form of starch or other similar materials, plasticizers such as PVA and also fillers in the form of fibers containing cellulose. The purpose of this study was to determine the effect of the combination of porang glucomannan, PVA and seaweed pulp on biofoam and to determine the best formulation and characteristics of the biofoam samples made.. The technique of making biofoam was done using baking technique with 9 different treatments. Each treatment was repeated 3x and observations were made on biofoam structure, mechanical properties testing (tensile strength, elongation and young modulus), water absorption test, and biodegradation test. The results showed that Polyvinyl Alcohol plays a role in the formation of a hollow biofoam structure. The thickness parameter value for each treatment was 0.628-1.939 mm. The tensile strength value of each treatment has a value ranging from 15.989-35.265 N/mm². The elongation value for each treatment ranged from 25.719-76.427%. The young modulus value for each treatment ranged from 0.343-0.896 N/mm². The water absorption value of each treatment obtained values ranging from 35.81-77.12%. And the value of testing biodegradation parameters obtained values ranging from 8.68-32.18%. So that the best treatment obtained using the multiple attribute method is the A3B1 treatment (PVA 15% and the ratio of seaweed pulp concentration to glucomannan 1: 2).

RETENTION OF FIRE WATER USED DURING FIREFIGHTING OPERATIONS BY THE FIRE BRIGADE

The article presents the issue of wastewater circulation after firefighting activities executedby fire brigades and the lack of research on the composition of water entering the city sewagesystem as well as the potential impact on the environment to which it is disposed of. It wasnoted that fire brigades use biodegradable foam agents during typical fire-fighting operations,both in sewage treatment plants and in the natural environment, but the main problem is theselection of fire-fighting techniques and extinguishing agents and the subsequent consequencesin the environment. Consideration was given to deciding whether to use water, which dissolvesflammable substances, foam containing surfactants, or completely refraining from extinguishingdue to the possibility of sewage entering the surrounding waters. To this end, it outlines the courseof fires where firefighting operations have resulted in the contamination of watercourses andbodies of water, contamination of the ground or long-term emission of toxic substances into theatmosphere. Due to the lack of guidelines for dealing with fire-water in urban conditions, attentionwas paid to absolute protection of watercourses and water bodies against the infiltration of postfiresewage in its original form and the use of mechanical dams and embankments to stop them atthe scene of the incident. Attention was also drawn to the proper operation of dosing equipmentand the environmental burden caused by using foam concentrates in higher concentrations thanrecommended by the manufacturer was presented.

Fabrication of Soft Biodegradable Foam with Improved Shrinkage Resistance and Thermal Stability.

The soft PBAT foam shows good flexibility, high elasticity, degradable nature, and it can be used as an environmental-friendly candidate for EVA and PU foams. Unfortunately, there are few reports on the application of PBAT as a soft foam. In this study, PBAT foam was fabricated by a pressure quenching method using CO2 as the blowing agent. A significant volume shrinkage of about 81% occurred, where the initial PBAT foam had an extremely high expansion ratio, of about 31 times. A 5-10 wt% PBS with high crystallinity was blended, and N2 with low gas solubility and diffusivity was mixed, with the aim of resisting foam shrinkage and preparing PBAT with a high final expansion ratio of 14.7 times. The possible mechanism behind this phenomenon was established, and the increased matrix modulus and decreased pressure difference within and outside the cell structure were the main reasons for the shrinkage resistance. The properties of PBAT and PBAT/PBS foams with a density of 0.1 g/cm3 were measured, based on the requirements for shoe applications. The 5-10 wt% PBS loading presented advantages in reducing thermal shrinkage at 75 °C/40 min, without compromising the hardness, elasticity, and the compression set, which ensures that PBAT/PBS foams have good prospects for use as soft foams.

Characteristics of Biodegradable Foam with Proportional Treatment of Tapioca Flour and Soybean Peel Flour with Added Glycerol

Characteristics of Biodegradable Foam with Proportional Treatment of Tapioca Flour and Soybean Peel Flour with Added Glycerol

Aerogel‐like biodegradable acoustic foams of bacterial cellulose

AbstractWe report the first work on the development of biodegradable acoustic foams from self‐grown bacterial cellulose (BC) from kombucha solution and green processing techniques. Kombucha BC‐agar and kombucha BC‐polyvinyl alcohol foams were fabricated by using slurries of BC pellicles mixed with the additives, froze for 24 h, and recast into foams using the freeze‐drying method. The foams were aerogel‐like with a density 20 kg/m3, thermally stable upto 220 °C, and crystallinity ~74%. Morphological analysis revealed macropores with coarse walls in agar‐based foams, whereas the PVA‐based foams comprised a polydisperse pore network with coarse walls. A broadband absorption was observed with a maximum of 0.4 for the 2.5‐mm‐thick single‐layer foams and 0.9 for the 12‐mm‐thick multilayer foams. The sound absorption was found to be on par with the biodegradable foams of agar and other cellulose‐rich materials such as agricultural residue, yet with a lightweight. Being largely porous, the foams had little transmission loss. As the densities and the crystallinities of these foams are tunable by the addition of other polymers, the results from this study provide scope to explore BC‐based lightweight materials for large‐scale fabrication suitable for sound absorption over specific regimes.

Development and characterization of biodegradable foam plates from corn starch and banana bunch stalks coated with beeswax

Development and characterization of biodegradable foam plates from corn starch and banana bunch stalks coated with beeswax

Biodegradable Foam from Cassava Starch Blended with Water Hyacinth Fiber: Effects of Polyvinyl Alcohol Content

Abstract Our previous investigation revealed that the addition of water hyacinth fiber (WHF) and polyvinyl alcohol (PVA) enhanced the mechanical properties of cassava starch-based foam. However, the effect of PVA concentration on the mechanical properties of starch foam is still unclear. Therefore, this study examined the effects of various concentrations of PVA on the foam’s quality and production process. Four levels of PVA (0, 1, 2, and 3% w/w) were tested on the mixed dough of cassava starch and 15% of WHF. The foam was made by baking the dough on a thermopressing machine at a temperature of 190 °C for 3 min. The quality level of foams was determined by their physical and mechanical (compressibility, water adsorption, density, color appearance, and biodegradability) properties as well as the practicality of the dough preparation and baking processes. As a result, the addition of PVA significantly affects the mechanical properties and ease of making dough. A higher concentration of PVA contributed to a better mixture of the dough, resulting in a smoother mixing process that led to foams with stronger mechanical properties. Nevertheless, the application of 2% and 3% PVA did not make a significant difference in the mechanical and physical properties. Foam with 2% PVA showed 32 N/mm2 of compressibility, 10% water absorptivity, 12% water content, and good biodegradability, with 87% of the material lost during 30 days of burial in the soil.

Overview of biodegradable polymers: synthesis, modification and application

Biodegradable polymeric represents a growing field. Owing to their wide-ranging properties, both synthetic and natural polymeric materials perform a vital and ubiquitous role in everyday life. Amended natural polymeric materials such as starch, cellulose, lignin, chitosan, cottonseed shell (CTS), and cotton gin trash (CGT) have enhanced properties, while synthetic Biodegradable polymeric materials such as poly (vinyl alcohol) (PVA), biodegradable plastics, biodegradable foams. Bioplastics are a kind of polymers able to be degraded by different microorganisms to small molecules (e.g., H2O, CO2, and CH4). Bioplastics are observed to solve waste materials and biodegradability is just a new material to be exploited at the end of its life in specific terms. They should be used for applications that require cheap methods to dispose of items after it has fulfilled their job (e.g., for food packaging, agriculture, or medical products).

Preparation of Shrink-Resistant Environmentally Friendly Foam

The shrinkage issue has posed a significant challenge for the practical application of biodegradable foam materials. The varying temperature-pressure mode (VT-PM) was adopted to fabricate poly (butylene adipate-butylene terephthalate) (PBAT)/Polybutylene succinate (PBS) foams. Foam shrinkage was significantly improved by the synergistic effect of temperature and pressure, and the shrinkage resistance mechanism was investigated by analyzing the cell structure. The crystallization behavior of PBS was investigated using differential scanning calorimetry (DSC) and polarized optical microscope (POM). Small size PBS crystals were obtained during the temperature change process, and the heterogeneous nucleation of PBS crystals increased the foaming expansion ratio. It was also found that the thick cell wall was able to act as a skeleton to support the structure of large cell size (＞100 μm) foams, ensuring larger compression stress and modulus.

Biodegradable flexible foam: Novel material based on cassava TPS obtained by extrusion

Thermoplastic foams made from petrochemical polymers are commonly commercialized in the market, which, due to their chemical nature, require hundreds of years to degrade and therefore end up accumulating and polluting the environment. Therefore, the present research sought to develop a biodegradable foam from thermoplastic cassava starch, biodegradable polyester, and wheat gluten. Initially, an extreme vertex blend design was run, which comprised 60 to 70% thermoplastic starch (TPS), 30 to 40% biodegradable polyester, and 0 to 5% wheat gluten, the foam was obtained by extrusion and evaluated for expansion rate, bulk density, damping index, and morphology. A thin layer of rubber latex was applied to the foamed material with the most outstanding properties in order to reduce moisture adsorption, and its biodegradability was also evaluated. The results indicated that with the addition of 70% TPS, 30% polyester, and 0% wheat gluten, it was possible to obtain by extrusion a flexible thermoplastic foam with high radial expansion rate and low bulk density. Impregnation of the foam with natural rubber latex created an impermeable layer that helped to decrease moisture adsorption; however, there was an increase in compressibility. Also, it was found that this foam met the biodegradability condition since it presented a percentage of mineralization in relative terms of 97.59% in less than 180 days.

Binder‐free, non‐carcinogenic surfactant‐based cellulose‐rich bagasse foams as acoustic panels

AbstractToward identifying environmentally friendly sound‐absorbing materials, the fabrication of biodegradable bagasse foams and their acoustic absorption and transmission loss were investigated. 10‐mm‐thick bagasse foams were fabricated using different concentrations of four non‐carcinogenic surfactants: sodium dodecyl sulfate (SDS), sodium bicarbonate (SB), potassium oleate (PO), and polyoxyethylene sorbitol ester (T20). Electron microscopy revealed that the foams comprised microfibers with a 10%–25% porosity. The foams were found to be thermally stable up to 300 °C. While foams fabricated using SDS were found to have a maximum increment in acoustic absorption (by 200%), those made of T20 had a mild decrease in absorption. The increment in absorption was attributed to the decrease in crystallinity and increase in porosity of microstructure, and the decrement to the decrease in viscous nature. Minimal changes were observed in the transmission loss of the foams. The results presented here demonstrate a simple, scalable green method to fabricate porous biodegradable foams of bagasse, without using any binder or filler, suitable for acoustic insulation that fits sustainable development objectives.

High energy absorption efficiency and biodegradable polymer based microcellular materials via environmental-friendly CO2 foaming for disposable cushioning packaging

Efficient energy absorption is crucial to ensure full protection on precision electronic devices during transportation. Hence, it is necessary to employ a substantial quantity of cushioning packaging materials, despite their disposable feature and severe environmental pollution impact. Therefore, an urgent need arises to develop a green and environmentally friendly material in its production and full life cycle and to offer high energy absorption for buffer packaging. In this study, two kinds of biodegradable components were selected, including a flexible chain structure to enhance the energy absorption capacity, and a rigid chain structure to provide effective support. By utilizing environmental-friendly supercritical CO2 foaming technology, a fully biodegradable foam was fabricated, which demonstrates great potential as a green buffer packaging material with the following advantages: (1) the material boasts a high energy absorption efficiency of 0.325, providing robust protection against the impact of external forces for precision devices during transportation; (2) its low thermal conductivity shields precision devices from heat shock; (3) as water contact angle exceeding 100°, the material changes from hydrophilic to hydrophobic, guarding against moisture erosion; (4) the introduction of cell structure accelerates the degradation process, further enhancing the material's environmental properties. Consequently, it is evident that the development of this innovative biodegradable material holds significant promise for advancing the existing environmentally friendly packaging material.

Fabrication of bio-based biodegradable poly(lactic acid) (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) composite foams for highly efficient oil-water separation

The open-cell bio-based biodegradable polymer foams show good application prospect in dealing with the serious environmental issue caused by oil spill and organic solvents spills, while the cell structures and hydrophobic properties of the foams limit their performance. In this work, the poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) was selected to help prepare bio-based biodegradable poly(lactic acid) (PLA) foams. Based on a two-step foaming method, the crystallization ability of different samples was regulated by the “original crystals” together with PHBV in the foaming process, where skeleton structures were provided to facilitate the open-cell structures and promote their mechanical property. As illustrated, PHBV facilitated the formation of open-cell PLA foams, where the foams displayed superior oil-water separation capacity. The maximum volume expansion ratio of the foams was 80.08, the contact angle of deionized water reached to 134.5°, the adsorption capacity for oil or organic solvents was 10.8 g/g-51.8 g/g, and the adsorption capacity for CCl4 can still maintained 83.5 % of the initial value after 10 adsorption-desorption cycles. This work not only clarified the foaming mechanism of open-cell foams, but also provided a green and simple method for preparing bio-based biodegradable foams possessing excellent oil-water separation performance.

Synthesis of Biofoam from Cassava Peel Starch, Banana Peel Starch and Chitosan as Additives

Biodegradable Foam (Biofoam) material has been made for application of styrofoam substitute food packaging material from a mixture of starch with chitosan as an additive. The purpose of this study was to determine the effect of molding temperature on biofoam products and to determine the effect of chitosan addition on the physical, mechanical, and biodegrability properties of biofoam made from cassava peel starch (a) and banana peel starch (b) which is close to commercial biofoam standards. The production of biofoam uses variations in molding temperature of 125, 150 and 175 °C and variations in chitosan weight with variations of 0, 1, 2 and 3 grams. The resulting biofoam product was then tested for density, water absorption, compressive strength, biodegradation and functional groups with Fourier Transform Infrared (FTIR). Based on the results of the study, it is known that biofoam that is close to commercial standards is found in the addition of 3 gr chitosan weight with a molding temperature of 125 °C with a density value of 0.423gr/cm3, water absorption of 42.54% and compressive strength of 0.0045 Mpa. As for biodegradation, biofoam products will decompose 55.17% for 55 days in 0 g chitosan weight with a thermopressing temperature of 175 °C. The spectrum results obtained on biofoam have C-H, C-O, C-N, N-H, C=O and O-H functional groups.

Characterisation of Gaina cocoon foam: A promising and eco-friendly alternative to synthetic materials

Increasing demand for polymeric foams, usually made of petroleum-based polymers, has raised concern about solid waste and its environmental impact, forcing scientists and researchers to find some biodegradable alternatives. However, these alternatives have limitations such as high density, more handling and processing costs, water and humidity-based degradation in cell structure, and inability to perform at elevated temperatures. This study discovers and examines a naturally occurring cellular material, the ‘Gaina’ cocoon, which is readily accessible in Uttarakhand hills and is inexpensive and biodegradable. Giana cocoon was found to have a density of 0.064 g/cc, which is lower than other natural biodegradable materials and very close to that of manufactured PLA foam. The morphological analysis revealed that the material has a cellular structure with irregularly shaped and sized cells. It has a semi-crystalline structure and is composed chiefly of carbon. Energy dispersive X-ray (EDX) spectroscopy showed that the Gaina cocoon foam has carbon and hydrogen as prime and major contributors. Fourier-transform infrared (FTIR) spectroscopy revealed various functional groups inside the cocoon, which will help understand its bonding with various matrices or materials. The differential scanning calorimeter (DSC) peak at 145°C was the largest (from 100°C to 181°C), showing a maximum heat transfer of about 278.325 J/g. The material is also thermally stable up to 260°C and has a lower density than other biodegradable foams on the market. Overall, these discoveries provide light on the features of this natural cellular material, which has potential uses in various industries, like packaging, insulation, and building.

Biodegradable nanofibrillated microcellular PBS/PLA foams for selective oil absorption

To address the challenges posed by spilled oil and oily wastewater, the development of clean oil-adsorption materials is crucial. However, traditional oil-adsorption materials suffer from the issue of secondary pollution. Herein, fully biodegradable nanofibrillated poly(butylene succinate)/poly(lactic acid) (PBS/PLA) foams with outstanding selective oil-adsorption performance were successfully fabricated via an eco-friendly supercritical CO2 foaming technology. The PBS/PLA composites, featuring nanofibrils with a diameter of approximately 100 nm, were prepared through a hot-stretching method subsequent to extrusion. Substantial improvements were observed in the crystallization rate and rheological properties of the fibrillated PBS/PLA composites. Furthermore, PLA nanofibrils enhanced foamability of the composite, achieving an impressive expansion ratio of up to 38.0, resulting in an outstanding oil-absorption performance (19.2–50.4 g/g) of the F-1 %-95 foam. Additionally, 20 adsorption-desorption cycles illustrated the prepared F-1 %-95 foam displayed recyclable oil-absorption characteristics. This work provides an eco-friendly strategy for preparing fully biodegradable foams intended for application as oil-adsorption materials.

Analisis Sifat Fisis dan Mekanik Biodegradable Foam Berbahan Dasar Selulosa Jerami Padi dan Polivinyl Alcohol

Research has been carried out on analyzing the physical and mechanical properties of biodegradable foam made from rice straw cellulose with a polyvinyl alcohol binding matrix. This study aims to produce a substitute for styrofoam, which is considered not environmentally friendly and harmful to health. The composition of straw fiber and polyvinyl alcohol was varied by the mass ratio of the mixture of rice straw fiber and PVA (%) 40:20%, 30:30%, 20:40%, 50:10%, with the size of the fiber passing through the 80 mesh sieve. The results of the characterization using FT-IR showed that the highest content of functional groups was carbon (C), which corresponds to the content of conventional biofoam, which consists of the elements carbon (C) and hydrogen (H). The highest biofoam tensile strength value is in the comparison fraction (20:40%) of 18.11 MPa. The highest percentage of biofoam water absorption was obtained in the fraction ratio (50:10%) of 0.8928% in the treated sample and 1.1928% in the untreated sample. The percentage of biofoam water content closest to conventional biofoam water content is obtained at a fraction ratio (40:20%) of 0.78%. The highest degradation rate was obtained in samples with a comparative fraction (50:10%) of 0.04237%/day in treated and 0.06403%/day in untreated samples. The results of this study stated that the resulting biofoam did not contain harmful substances. After identifying the functional groups using the FT-IR test, the tensile strength of biofoam still did not meet the SNI 7188.7: 2016 bioplastic standard.

Sintesis Selulosa Asetat dari Ampas Tebu sebagai Bahan Baku Biodegradable Foam

The high cellulose content of bagasse allows it to be developed into a variety of valuable products, one of them is cellulose acetate which will be used to make biodegradable foam. The purpose of this research is to determine the best conditions for the synthesis of cellulose acetate from bagasse and test how cellulose acetate can be used to make biodegradable foam. This study used phosphoric acid as a solvent and glacial acetic acid as an acetylating agent to make cellulose acetate through the acetylation process. The variations in acetylation time in this study were 15, 30, and 45 minutes and the volume of glacial acetic acid as acetylating agent was 20, 40, 60, 80, and 100 ml. The results of this study indicated that the optimum conditions for the synthesis of cellulose acetate are 15 minutes of acetylation with a volume of 100 ml of glacial acetic acid, with a yield of 79.31% cellulose acetate, 36.19% acetyl content and a degree of substitution of 2.11. The test for the application of cellulose acetate to make biodegradable foam obtained a water absorption of 18.81%, the biodegradation test obtained was 24.53% in 14 days. In the biodegradable foam leak test for 10 minutes, no leakage occurred. This indicated that the biodegradable foam obtained was suitable to use because it complied with SNI.