Melting Processing of Biodegradable Cellulose Diacetate/Starch Composites

Tensile and Surface Wettability Properties of the Solvent Cast Cellulose Fatty Acid Ester Films

Thermoplastic cellulose esters are promising materials for bioplastic packaging. For that usage, it is important to understand their mechanical and surface wettability properties. In this study, a series of cellulose esters are prepared, such as laurate, myristate, palmitate, and stearate. The aim of the study is to investigate the tensile and surface wettability properties of the synthesized cellulose fatty acid esters to understand their suitability as a bioplastic packaging material. Cellulose fatty acid esters are first synthesized from microcrystalline cellulose (MCC), then dissolved in pyridine solution, and after the solvent cast into thin films. The cellulose fatty acid ester acylation process is characterized by the FTIR method. Cellulose esters hydrophobicity is evaluated with contact angle measurements. The mechanical properties of the films are tested with the tensile test. For all the synthesized films, FTIR provides clear evidence of acylation by showing the presence of characteristic peaks. Films' mechanical properties are comparable to those of generally used plastics such as LDPE and HDPE. Furthermore, it appears that with an increase in the side-chain length, the water barrier properties showed improvement. These results show that they could potentially be suitable materials for films and packaging materials.

Glucaric acid additives for the antiplasticization of fibers wet spun from cellulose acetate/acetic acid/water

Cellulose acetate (CA) receives notable attention as an environmentally friendly, biodegradable polymer from renewable, low-cost resources. CA polymers are believed to have a critical role in shaping a greener and more circular textile economy. However, the mechanical properties of CA fibers are among the lowest in terms of its tensile strength, poor wet strength, and low flexural strength. This study investigates the effect of biobased additives for antiplasticizing the mechanical performance and structure of CA fibers. At up to 5 % of CA, glucaric acid (GA) and its monoammonium salt were added to CA fibers. With 1.5 % GA additive, tensile modulus improved by 155%, tensile strength by 55 %, and CA flexibility according to knot to straight fiber tenacity ratios improved by 107 % when compared to neat CA fibers. Based on the results, green small molecule antiplasticizers do exist, but their performance improvements are observed at low percentages of loading.

Development of corn starch based green composites reinforced with Saccharum spontaneum L fiber and graft copolymers--evaluation of thermal, physico-chemical and mechanical properties

In this paper, corn starch based green composites reinforced with graft copolymers of Saccharum spontaneum L. (Ss) fiber and methyl methacrylates (MMA) and its mixture with acrylamide (AAm), acrylonitrile (AN), acrylic acid (AA) were prepared. Resorcinol-formaldehyde (Rf) was used as the cross-linking agent in corn starch matrix and different physico-chemical, thermal and mechanical properties were evaluated. The matrix and composites were found to be thermally more stable than the natural corn starch backbone. Further the matrix and composites were subjected for biodegradation studies through soil composting method. Different stages of biodegradation were evaluated through FT-IR and scanning electron microscopic (SEM) techniques. S. spontaneum L fiber-reinforced composites were found to exhibit better tensile strength. On the other hand Ss-g-poly (MMA) reinforced composites showed maximum compressive strength and wear resistance than other graft copolymers reinforced composite and the basic matrix.

Green composite films prepared from cellulose, starch and lignin in room-temperature ionic liquid

A series of novel biobased composite films derived from cellulose, starch and lignin were prepared from an ionic liquid (IL), 1-allyl-3-methylimidazolium chloride (AmimCl) by coagulating in a nonsolvent condition. The ionic liquid can be recycled with a high yield and purity after the green film was prepared. The uniform design method was applied to investigate mechanical properties of the biobased composite films. The effect of each component and their associated interactive effects were investigated. The experimental results showed that contents of cellulose, lignin and starch had a significant influence on the mechanical properties of composite films. The composite films showed relatively excellent mechanical properties in dry and wet states owing to the mutual property supplement of different components. The composite films were characterized via FT-IR, X-ray diffraction (XRD) and scanning electron microscope (SEM). Their thermal stability and gas permeability were also investigated, and the results showed that the composite films had good thermal stability and high gas barrier capacity and give a CO(2):O(2) permeability ratio close to 1.