Antioxidant and physicochemical properties of blended films based on gelatin‐sodium caseinate activated with natural extracts

Blend films of pigskin gelatin (GEL) and sodium caseinate (SCas) with boldo (B), guarana (G), cinnamon (C), or rosemary (R) extracts added were studied. SCas and extracts addition in blend films significantly increased the gloss and better UV barrier of GEL100 films. Extracts incorporation significantly decreased the rigidity and elongation of GEL100 films, which were significantly improved in GEL75:SCas25 blend films with extracts (EM = 295.69 ± 21.75 MPa and EB = 11.60 ± 3.43%). SCas addition not affected the TS parameter. The water vapor permeability of GEL100 films was reduced in blended films with extracts, showing the lowest value for GEL75:SCas25 + R (0.99 ± 0.07 × 10¹⁰ g s^?1 m^?1 Pa^?1). FTIR and microstructure analyses showed good compatibility for all components. The antioxidant activity of GEL100 was significantly increased with SCas and extracts addition (GEL50:SCas50 + R = 4.31 ± 0.11 mM ), suggesting the application of these films as an active food packaging material. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44467.     

Ultra‐microstructural features of perborate oxidized starch

Ultrafine structures of low, medium, and highly oxidized starches, symbolized as LOS, MOS, and HOS, respectively, were thoroughly investigated. These oxidized starches were obtained by treatment of native starch (NS) with three different concentrations of sodium perborate (SPB). Thus, obtained products were studied with respect to major chemical and fine physical characteristics vis‐a‐vis these of NS (a) acidic and reduced groups creation along with mode of association, (b) significant increase in solubility, and (c) outstanding decrease in apparent viscosity. Thermogravimetric analysis (TGA) revealed thermal stability of the said substrates follows order: HOS > MOS > LOS > NS. Scanning electron micrographs (SEM) showed polygonal or irregular shape with particle size ranging from 2 to 20 μ. After oxidation, the starch surface became rough and the edges lost their definiteness completely. In conclusion, SPB is an efficient oxidant to produce oxidized starches with useful characteristics, which advocate them to wide applications in textile sizing and medicinal domains. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40170.     

Spray‐drying microencapsulation of β‐carotene by soy protein isolate and/or OSA‐modified starch

Microencapsulation is an effective strategy to improve the storage stability of β‐carotene. This article investigated the potential and effectiveness of soy protein isolate (SPI) and octenylsuccinic anhydride‐modified starch (MS), alone or in combination (1:1, w/w), to encapsulate β‐carotene by spray drying. The results indicated that the microcapsule with MS exhibited much lower encapsulation efficiency (NE) and poorer dissolution behavior, but much better redispersion behavior, than that with SPI or its blends with MS. The NE was basically unaffected by total solid content (TC) or core/wall ratio; increasing the TC impaired the dissolution and/or redispersion behavior. The dispersion behavior was closely associated with the morphology of the microcapsules. The encapsulated β‐carotene suffered a progressive loss upon storage under high humid or temperature environment, but it exhibited extraordinary stability at low temperatures (e.g., 4°C). The β‐carotene degradation was independent of sunlight. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40399.     

New alginate foams: Box‐Behnken design of their manufacturing; fire retardant and thermal insulating properties

A new method for preparing alginate foams with progressive release of copper in the presence of sodium lauryl sulfate (SLS, foaming agent) has been designed. Copper acts as the ionotropic gelling agent through the reaction of copper carbonate with gluconolactone. The process does not require freeze‐drying contrarily to the conventional method used for preparing macroporous alginate foams. The new materials investigated in this study have remarkable thermal properties, including thermal conductivity lower than 0.041 W m^?1 K^?1 and low heat release (below 2 kJ g^?1), which allows labeling these foams self‐extinguishing materials. An experimental design methodology, based on a Box‐Behnken plan with three parameters and three levels, is successfully used for evaluating the impact of the amounts of alginate, SLS, and copper carbonate on the productivity, apparent density, and shrinking at air‐drying. It yielded an optimization of the process for the manufacturing of light, and stable/rigid insulating and thermally stable materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45868.     

Impact of the coating process on the molecular structure of starch‐based barrier coatings

Molecular analysis of starch structure can be used to explain and predict changes in physical properties, such as water vapor and oxygen barrier properties in packaging materials. Solution casting is a widely used technique to create films from starch formulations. This study compared the molecular properties of these standard films with those of experimental coatings applied to paper in laboratory‐scale and pilot‐scale trials, with all three techniques using the same starch formulation. The results revealed large differences in molecular structure, i.e., cross‐linking and hydrolysis, between films and coatings. The main differences were due to the shorter drying time allowed to laboratory‐scale coatings and the accelerated drying process in pilot trials owing to the high energy output of infrared dryers. Furthermore, surface morphology was highly affected by the coating technique used, with a rougher surface and many pinholes occurring in pilot‐scale coatings, giving lower water vapor permeability than laboratory‐scale coatings. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41190.     

Synthesis,characterization, and properties of acrylate‐modified tung‐oil waterborne insulation varnish

An acrylate‐modified tung‐oil waterborne insulation varnish was synthesized from tung oil, maleic anhydride, and acrylates via a Diels–Alder reaction and free‐radical polymerization, and the varnish could be solidified at a relatively low temperature with blocked hexamethylene diisocyanate as a curing agent. The resulting films were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. The insulation properties (electrical insulation strength, volume resistivity, and surface resistivity) of the varnish films were tested, and the resistances of films to salted water were evaluated. With an increase in the maleic anhydride content, the thermal stability of the film was improved, whereas the electrical insulation strength, volume resistivity, and surface resistivity decreased. The electrical insulation strength of the film after it was immersed in the NaCl solution was lower than that in dry state, and it decreased as the immersed time was prolonged. In particular, the electrical insulation strength loss of the film increased significantly at maleic anhydride contents beyond 25 wt %. Furthermore, the hardness of the film increased with increasing methyl methacrylate/N‐butyl acrylate ratio, whereas the flexibility and adhesion of film decreased to a certain degree at the same time. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41608.     

Bio‐nanocomposite films based on cellulose nanocrystals filled polyvinyl alcohol/chitosan polymer blend

Bio‐nanocomposite films based on polyvinyl alcohol/chitosan (PVA/CS) polymeric blend and cellulose nanocrystals (CNC) were prepared by casting a homogenous and stable aqueous mixture of the three components. CNC used as nanoreinforcing agents were extracted at the nanometric scale from sugarcane bagasse via sulfuric acid hydrolysis; then they were characterized and successfully dispersed into a PVA/CS (50/50, w/w) blend to produce PVA/CS–CNC bio‐nanocomposite films at different CNC contents (0.5, 2.5, 5 wt %). Viscosity measurement of the film‐forming solutions and structural and morphological characterizations of the solid films showed that the CNC are well dispersed into PVA/CS blend forming strong interfacial interactions that provide an enhanced load transfer between polymer chains and CNC, thus improving their properties. The obtained bio‐nanocomposite films are mechanically strong and exhibit improved thermal properties. The addition of 5 wt % CNC within a PVA/CS blend increased the Young's modulus by 105%, the tensile strength by 77%, and the toughness by 68%. Herein, the utilization of Moroccan sugarcane bagasse as raw material to produce high quality CNC has been explored. Additionally, the ability of the as‐isolated CNC to reinforce polymer blends was studied, resulting in the production of the aforementioned bio‐nanocomposite films with improved properties. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42004.     

Sophorolipid‐induced dimpling and increased porosity in solvent‐cast short‐chain polyhydroxyalkanoate films: Impact on thermomechanical properties

Sophorolipids (SL; microbial glycolipids) were used as additives in solvent‐cast short‐chain polyhydroxyalkanoate (sc‐PHA) films to enhance surface roughness and porosity. Poly‐3‐hydroxybutyrate (PHB), poly‐(6%)‐3‐hydroxybutyrate‐co‐(94%)‐3‐hydroxyvalerate (PHB/V), and poly‐(90%)‐3‐hydroxybutyrate‐co‐(10%)‐3‐hydroxyhexanoate (PHB/HHx) films were evaluated with up to 43 wt % of SL. Sophorolipid addition caused surface dimples with maximum diameters of 131.8 µm (PHB), 25.2 µm (PHB/V), and 102.8 µm (PHB/HHx). A rise in the size and number of pores in the polymer matrix also occurred in PHB and PHB/V films. Surface roughness and film porosity were visualized by scanning electron microscopy and quantitated using confocal microscopy by correlating the surface area (A′) to the scanned area (A) of the films. The phenotypic alterations of the films caused a gradual decline in tensile strength and modulus and increased the elongation to break. Reductions in the enthalpies of fusion (ΔH_f) in both the PHB (41% reduction) and PHB/HHx (36% reduction) films implied diminished crystallinity as SL concentrations increased. Over the same SL concentrations the Tan δ maxima shifted from 4 to 30°C and from 2 to 20°C in these respective films. These results provide a novel means by which sc‐PHA properties can be controlled for new/improved applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40609.     

Studies on the thermal and mechanical behavior of PLA‐PET blends

The increasing use of bio‐sourced and biodegradable polymers such as poly(lactic acid) (PLA) in bottle packaging presents an increasing challenge to the polyethylene terephthalate (PET) recycling process. Despite advanced separation technologies to remove PLA from PET recyclate, PLA may still be found in rPET process streams. This study explores the effects of PLA on the mechanical properties and crystallization behavior of blends of PET containing 0.5–20% PLA produced by injection molding. SEM indicates an immiscible blend of the two polymers and TGA confirms the independent behavior of the two polymers under thermal degradation conditions. Temperature‐modulated DSC studies indicate that adding PLA to PET increases the rigid amorphous fraction of the PET moiety. Critical amounts of PLA induce stress oscillation behavior during mechanical testing. The mechanical behavior of the samples is explained by antagonistic interaction between increased rigid amorphous fraction and decreased fracture strength arising from an increased population of PLA microparticles. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44147.     

Active packaging material based on buriti oil – Mauritia flexuosa L.f. (Arecaceae) incorporated into chitosan films

Active and biodegradable materials have great potential in food packaging applications, improving the safety and quality of products. The objective of this study was to develop a new material based on buriti oil incorporated into a chitosan film. Different concentrations of buriti oil in dried films (2.1 g/m², 10.4 g/m², 20.8 g/m², and 31.3 g/m²) were added into a chitosan matrix (41.7 g/m²). The chitosan/buriti oil films were characterized by water‐vapor barrier properties, total water‐soluble matter (TSM), tensile properties, thermogravimetric analysis, microstructure, microbial permeation properties, and biodegradation estimation. The higher oil concentration improved the water‐vapor barrier and the buriti oil acted largely as a plasticizer and increased the elongation at break, and decreased the tensile strength (TS) of chitosan films. The total water‐soluble matter of chitosan films decreased in function of the buriti oil concentration, but the biodegradation and thermal stability increased. The chitosan films presented a microbial barrier against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43210.     

Preliminary evaluation of packaging‐content interactions: Mechanical and physicochemical characterization of polylactide bottles

Biodegradable materials as polylactide (PLA) are very interesting for cosmetic packaging application. However, these polymers, under environmental conditions or/and chemical treatments, can undergo “aging,” compromising their performances such as container. The aim of this study was the evaluation of mechanical, physicochemical, and organoleptic properties of PLA bottles present in the cosmetic market. In particular, mechanical tests and thermal analyses were applied to study the PLA container degradation under stressed physicochemical conditions. Calorimetric and morphological analyses were applied to evaluate differences between internal and external surface of containers. Results highlighted that the heating process together with chemical treatment determined a significant modification on polymer, leading to a more resistant and fragile material, whereas the only physical or chemical treatment alone showed a plasticizing effect. In conclusion, this study represents a start point to evaluate content–packaging interactions to optimize the choice of PLA polymer as cosmetic packaging. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40067.     

Processing and properties of polypropylene‐based composites containing inertized fly ash from municipal solid waste incineration

This article reports for the first time the results about the use of inertized fly ash from municipal solid waste incineration as a filler for polypropylene (PP). An innovative process based on the stabilization with colloidal silica has been used for fly ash inertization. Polymer–filler composites containing different filler amounts up to 30 wt % have then been formulated and prepared by means of melt compounding process. Structural, morphological, mechanical, and thermal characterization of their properties has been performed and discussed in detail. Remarkable enhancements of tensile (+ 93%) and flexural (+ 107%) elastic moduli if compared to pristine PP, together with enhancements of flexural resistance (+ 36%) and deflection temperature under load (+ 50%), have been observed when adding filler 30 wt % in suitable processing conditions. Moreover the filler has been shown to interact with polymer crystalline structure and positively influence the thermal‐oxidative stability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4157–4164, 2013     

Physico‐chemical,thermal, and mechanical approaches for the characterization of solubilized and solid state chitosans

This study was conducted on the both solid and solubilized chitosans to propose an approach for the physico‐chemical, thermal and mechanical characterizations of this polysaccharide. The polysaccharide used was a 90% deacetylated chitosan having a molecular weight of 98.4 kDa. The flow property of chitosan solutions was evaluated revealing a shear‐thinning behavior. The thermal characterization was carried out by studying heat specific capacity, glass transition temperature, and thermal conductivity on chitosan dried specimens (solid state). Their T_g were measured by DSC and confirmed by DMA at 102 and 122°C depending on concentrations of initial chitosan solutions. The mechanical characterization was conducted by analyzing Young modulus, tensile strength, and elongation at break of chitosan specimens. They exhibited a higher elongation at break and a lower tensile strength when made from high concentrated chitosan solution (9% w/v). Differences in mechanical behavior of specimens were explained by differences of crystallinity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41257.     

Improvement of the thermal properties of poly(3‐hydroxybutyrate) (PHB) by low molecular weight polypropylene glycol (LMWPPG) addition

In this work, blends of poly(3‐hydroxybutyrate) (PHB) with 5, 10, 15, and 20 wt % low molecular weight poly(propylene glycol) (LMWPPG) have been prepared and characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) with attenuated total reflectance (ATR) accessory and simultaneous thermal analysis (TG/DTA). FTIR and thermal analyses suggested that the presence of LMWPPG led to a maximum crystallinity for the blend PHB/PPG (90/10) blend. The presence of LMWPPG also caused a significant increase of the PHB processability window, i.e., the difference of the melting and degradation temperature, of PHB from 105 to 134°C, which is extremely important for the industrial uses of PHB. This PHB stabilization effect is discussed in terms of an intermolecular interaction of the PHB carbonyl with LMWPPG methyl groups which probably hinders the classical radon β‐scission PHB intramolecular decomposition mechanism. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Evaluation of 1‐ethyl‐3‐methylimidazolium acetate based ionic liquid systems as a suitable solvent for collagen

Collagen, a prominent biopolymer, which is famous for its excellent biological activity, has been used extensively for tissue engineering applications. In this study, a novel solvent system for collagen was developed with an ionic liquid, 1‐ethyl‐3‐methylimidazolium acetate ([EMIM][Ac]), solvent system. A series of sodium salts were introduced into this solvent system to enhance collagen's dissolution procedure. The results show that the solubility of collagen was significantly influenced by the temperature and sodium salts. The solubility reached up to approximately 11% in the [EMIM][Ac]/Na₂HPO₄ system at 45°C. However, the structure of the regenerated collagen (Col‐regenerated) may have been damaged. Hence, we focused on the structural integrity of the collagen regenerated from the [EMIM][Ac] solvent system by the methods of sodium dodecyl sulfate–polyacrylamide gel electrophoresis, Fourier transform infrared spectroscopy, ultrasensitive differential scanning calorimetry, atomic force microscopy, X‐ray diffraction, and circular dichroism because its signature biological and physicochemical properties were based on its structural integrity. Meanwhile, a possible dissolution mechanism was proposed. The results show that the triple‐helical structure of collagen regenerated from the [EMIM][Ac] solvent system below 35°C was retained to a large extent. The biocompatibility of Col‐regenerated was first characterized with a fibroblast adhesion and proliferation model. It showed that the Col‐regenerated had almost the same good biological activity as nature collagen, and this indicated the potential application of [EMIM][Ac] in tissue engineering. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2245–2256, 2013     

Electrical conduction in plasma polymerized thin films of γ‐terpinene

Plasma polymerized γ‐terpinene (pp?GT) thin films are fabricated using RF plasma polymerization. MIM structures are fabricated and using the capacitive structures dielectric properties of the material is studied. The dielectric constant values are found to be in good agreement with those determined from ellipsometric data. At a frequency of 100 kHz, the dielectric constant varies with RF deposition power, from 3.69 (10 W) to 3.24 (75 W). The current density–voltage (J?V) characteristics of pp–GT thin films are investigated as a function of RF deposition power at room temperature to determine the resistivity and DC conduction mechanism of the films. At higher applied voltage region, Schottky conduction is the dominant DC conduction mechanism. The capacitance and the loss tangent are found to be frequency dependent. The conductivity of the pp?GT thin films is found to decrease from 1.39 × 10^?12 S/cm (10 W) to 1.02 × 10^?13 S/cm (75 W) and attributed to the change in the chemical composition and structure of the polymer. The breakdown field for pp–GT thin films increases from 1.48 MV/cm (10 W) to 2 MV/cm (75 W). A single broad relaxation peak is observed indicating the contribution of multiple relaxations to the dielectric response for temperature dependent J?V. The distribution of these relaxation times is determined through regularization methods. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42318.     

Bio‐inspired “green” nanocomposite using hydroxyapatite synthesized from eggshell waste and soy protein

Eco‐friendly and inexpensive “ green” nanocomposites with enhanced functional performances were developed by combining nanoscale hydroxyapatite (HA) synthesized from eggshell waste (nEHA) and protein‐based polymer extracted from defatted soybean residues. nEHA was synthesized from chicken eggshells using an energy efficient microwave‐assisted wet chemical precipitation method. Transmission electron microscopy, X‐ray diffraction, and energy‐dispersive X‐ray spectroscopy studies confirmed the nanometer scale (diameter: 4–14 nm and length: 5–100 nm) of calcium‐deficient (Ca/P ratio ～1.53) needle‐like HA. Uniform dispersion of nEHA in soy protein isolate (SPI) solution was obtained by modifying nEHA surface using a polyelectrolyte (sodium polyacrylate) dispersant via irreversible adsorption. Green nanocomposite films were prepared from SPI and surface‐modified nEHA with the help of a natural plasticizer “glycerol” by solution casting. Significant improvements in tensile modulus and strength were achieved owing to the inclusion of uniformly dispersed nEHA in SPI sheets. Overall, this work provides a green pathway of fabricating nanocomposites using naturally occurring renewable polymer and inorganic moieties from eggshell waste that emphasizes the possibilities for replacing some petroleum‐based polymers in packaging and other applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43477.     

Synthesis and properties of cross‐linked polymers from epoxidized rubber seed oil and triethylenetetramine

A series of epoxidized oils were prepared from rubber seed, soybean, jatropha, palm, and coconut oils. The epoxy content varied from 0.03 to 7.4 wt %, in accordance with the degree of unsaturation of the oils (lowest for coconut, highest for rubber seed oil). Bulk polymerization/curing of the epoxidized oils with triethylenetetramine (in the absence of a catalyst) was carried out in a batch setup (1 : 1 molar ratio of epoxide to primary amine groups, 100°C, 100 rpm, 30 min) followed by casting of the mixture in a steel mold (180°C, 200 bar, 21 h) and this resulted in cross‐linked resins. The effect of relevant pressing conditions such as time, temperature, pressure, and molar ratio of the epoxide and primary amine groups was investigated and modeled using multivariable nonlinear regression. Good agreement between experimental data and model were obtained. The rubber seed oil‐derived polymer has a T_g of 11.1°C, a tensile strength of 1.72 MPa, and strain at break of 182%. These values are slightly higher than for commercial epoxidized soybean oil (T_g of 6.9°C, tensile strength of 1.11 MPa, and strain at break of 145.7%). However, the comparison highlights the potential for these novel resins to be used at industrial/commercial level. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42591.     

Polylactic acid and its blends with petroleum‐based resins: Effects of reprocessing and recycling on properties

Environmental and economic reasons make the use of bioplastics and biocomposites increasingly coveted in sectors other than packaging. Recycling of all wasted or rejected durable plastics is highly desired and biobased plastics are no exception. Therefore, the investigation of pre‐ and post‐consumer recycling of products made from biobased plastics is of great interest. Polylactic acid (PLA) and its blends have been chosen for this study because it is an excellent representative of mass‐produced bioplastics for industrial applications. As part of the “Sustainable Recycling of ‘Green’ Plastics” project, the current study addresses the durability issues related to the reprocessing and post‐consumer recycling of a PLA virgin resin and two commercially available blends of PLA namely one with polycarbonate (PC) and one with polyethylene (PE). The materials were investigated using methods that simulate post‐processing and post‐consumer recycling. Accelerated ageing was performed at elevated temperature and humidity to simulate the usage period of the materials. The materials were analyzed using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and their mechanical strength was evaluated by tensile and impact testing. The flow properties of the materials were characterized by the melt flow index (MFI). Multiple processing of pure PLA did not affect the impact strength or the glass transition temperature (T_g), but caused crystallization and increase in the MFI, indicating that degradation occurred during processing. DSC thermograms of the blends revealed that the components in the blends were not miscible. Multiple processing of the blends did not significantly affect the elastic modulus of the materials, but affected the elongation at break. The results indicated that multiple processing of the PLA/HDPE blend caused increased dispersion and thus increased elongation at break, while the dominating mechanism in the PLA/PC blend was degradation that caused a decrease in elongation at break. Post‐consumer recycling of the PLA/PC blend was simulated and the results clearly showed that ageing corresponding to one year of use caused a significant degradation of PLA. Pure PLA was severely degraded after only one ageing cycle. Although the PLA/PC blend showed some improved mechanical properties and resistance to degradation compared with pure PLA, one ageing cycle still caused a severe degradation of the PLA and even the PC was degraded as indicated by the formation of small amounts of bisphenol A. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43916.     

“True” biocomposites with biopolyesters and date seed powder: Mechanical,thermal, and degradation properties

Biopolymers have gained research focus due to enhanced property profiles as well as need to replace the fossil fuel based polymeric materials. The generation of biocomposites with functional biofillers can lead to further enhancement of their potential. In this study, composites of date seed powder with biopolyesters poly(butylene adipate‐co‐terephthalate) (PBAT) and poly‐l ‐lactide (PLA) have been demonstrated. The composites exhibited individual degradation peaks for the components in the thermogravimetric analysis (TGA), but still had suitable thermal performance confirmed by the dynamic TGA. The filler also modified the crystalline morphology of the polymers differently. The tensile modulus of the PBAT‐based composites had enhancement of more than 300% in the composite with 40% filler content. The PLA composites also enhanced the modulus marginally till 20% filler content, however, it was still significant due to the very high modulus of PLA as compared to PBAT. The rheological properties indicated the polymer still had viscous behavior even when high amount of filler was added. The storage and loss modulus of the composites enhanced with filler fraction, the PLA composites with 30 and 40% content, however, exhibited very high values probably due to filler aggregates and low filler‐polymer interfacial interactions. The filler particles were observed to be uniformly distributed in the polymer matrices, though some filler aggregates were also observed in the composites with higher filler fractions. After embedding in compost soil, the composites had significantly enhanced extent of biodegradation as compared to pure polymers, thus, confirming the “true” biocomposite nature. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40816.