The Effect of Varying Almond Shell Flour (ASF) Loading in Composites with Poly(Butylene Succinate (PBS) Matrix Compatibilized with Maleinized Linseed Oil (MLO)

Abstract

In this work poly(butylene succinate) (PBS) composites with varying loads of almond shell flour (ASF) in the 10–50 wt % were manufactured by extrusion and subsequent injection molding thus showing the feasibility of these combined manufacturing processes for composites up to 50 wt % ASF. A vegetable oil-derived compatibilizer, maleinized linseed oil (MLO), was used in PBS/ASF composites with a constant ASF to MLO (wt/wt) ratio of 10.0:1.5. Mechanical properties of PBS/ASF/MLO composites were obtained by standard tensile, hardness, and impact tests. The morphology of these composites was studied by field emission scanning electron microscopy—FESEM) and the main thermal properties were obtained by differential scanning calorimetry (DSC), dynamical mechanical-thermal analysis (DMTA), thermomechanical analysis (TMA), and thermogravimetry (TGA). As the ASF loading increased, a decrease in maximum tensile strength could be detected due to the presence of ASF filler and a plasticization effect provided by MLO which also provided a compatibilization effect due to the interaction of succinic anhydride polar groups contained in MLO with hydroxyl groups in both PBS (hydroxyl terminal groups) and ASF (hydroxyl groups in cellulose). FESEM study reveals a positive contribution of MLO to embed ASF particles into the PBS matrix, thus leading to balanced mechanical properties. Varying ASF loading on PBS composites represents an environmentally-friendly solution to broaden PBS uses at the industrial level while the use of MLO contributes to overcome or minimize the lack of interaction between the hydrophobic PBS matrix and the highly hydrophilic ASF filler.

Effect of Almond Shell Waste on Physicochemical Properties of Polyester-Based Biocomposites

“…According to other authors, cellulose, hemicelluloses and lignin show a broad temperature range starting at about 250 • C and ending at 450 • C in a progressive weight loss process, and this degradation can reduce the thermal stability of biopolyesters [43][44][45]. Similar findings were reported by Liminana et al [31] who observed a decrease of 11.2 • C in thermal stability of PBS with the addition of 30 wt % of almond shells. The addition of MLO (Figure 5c,d) exerted a limited positive effect on the overall thermal stability of the biocomposites (Table 3).…”

“…Recently, vegetable oils have been proposed as environmentally friendly compatibilizers as an alternative to conventional petroleum-based ones [29]. Specifically, maleinized linseed oil (MLO) has been used as a compatibilizer in biopolymer/ASP composites [11,30,31]. In these works, authors discussed plasticization and compatibilization effects provided by MLO due to the interaction between succinic anhydride polar groups contained in MLO and hydroxyl groups in ASP (hydroxyl groups in cellulose).…”

Poly(lactic acid) green composites filled with linseed cake as an agricultural waste filler. Influence of oil content within the filler on the rheological behavior

“…The second trend in the development of natural composites is the application of powder‐like fillers, mostly ground waste lignified parts of various plants, whose application allows to significantly reduce the final product's price . The application of ground husks, cobs, shells, and seeds has become attractive mostly due to their high local availability and low cost . It should be mentioned that apart from cost‐effectiveness, natural waste fillers may serve as modifiers of PLA matrix, with a reinforcing or plasticizing effect.…”

Influence of modified fiber–MHSH hybrids on fire hazards, combustion dynamics, and mechanical properties of flame‐retarded poly(butylene succinate) composites

“…[3][4][5] Therefore, PBS is a type of ideal plastic matrix for the preparation of biodegradable composites. 7,8 Nonetheless, natural fibers and PBS are both flammable. The environmental-friendly PBS/wood-plastic composites (WPCs) are prepared by blending PBS with wood fiber, which can effectively reduce the cost of PBS and alleviate the threat of oil crisis and white pollution.…”

“…The environmental-friendly PBS/wood-plastic composites (WPCs) are prepared by blending PBS with wood fiber, which can effectively reduce the cost of PBS and alleviate the threat of oil crisis and white pollution. 7,8 Nonetheless, natural fibers and PBS are both flammable. 9,10 The WPC without flame retardant modification may cause serious fire safety hazard.…”