Table 2.

Thermal, mechanical, barrier, and other interesting properties of biocomposite films

Biopolymer	Filler and concentration	Processing technology	Thermal properties (°C)	Mechanical properties	Water vapor barrier	Other interesting properties	References
Cellulose	Napier grass cellulose fibrils (NGCFs) (0, 5, and 25%wt)	Casting solution	TDa = 358 − 363	σme = 49.7–107.9 MPa εBf = 7.8–12.7%	-	Good interaction filler-matrix Random orientation of NGCFs	[120]
Microfibrillated cellulose	Kaolin clay and calcium carbonate (0, 2.5, 5, 7.5, and 10%wt)	Casting solution	-	-	1.04–2.49 10−2 gm/(m2 day)	Low density	[271]
Nanocellulose	Barium titanate nanoparticles (0, 30, 40, 50, and 60%wt)	Casting solution	TDa ⋍ 300	-	-	Dielectric/electrical property Piezoelectric performance	[272]
Thermoplastic starch	Carbon ashes (0, 7, 14, and 21%wt)	Melt mixing and compression molding	Tmb = 167.51–191.95 Tgc = 97.70–146.37	Ed = 27.87–32.19 MPa σme = 2.27–2.65 MPa εBf = 33–66%	-	Degree of crystallinity = 12.7–22.2% Ashes decreased 70% the starch deterioration	[246]
Thermoplastic starch	Talc nanoparticles (0–5%wt)	Melt mixing and thermocompression	TDa = 255–275 Tm = 144.3–156.4 Tg1c = -51.8–(− 45.4) Tg2c = 45.9–46.9	Ed = 22.7–38.2 MPa σme = 1.19–2.34 MPa εBf = 59.0–62.2%	0.6–1.3 10−10 g/(m s Pa)	Degree of crystallinity = 5.4–5.6% Oxygen permeation = 388.7–527.8 cm3 mil/(m2 day) Thermosealing capacity	[244, 273, 274]
Thermoplastic starch	Bentonite particles (0–5%wt)	Melt mixing and thermocompression	Tmb = 98.5–96.9 Tgc =  − 66.3–(− 65.0)	Ed = 50.9–180.9 MPa σme = 1.96–3.89 MPa εBf = 38.4–96.2%	-	Degree of crystallinity = 5.6–9.6% Eventual particles intercalation	[161, 275]
Thermoplastic starch	Granite sand particles (0, 1, and 5%wt)	Melt mixing and thermocompression	TDa = 317–321 Tmb = 147.4–161.2	Ed = 80–405 MPa σme = 1.8–5.6 MPa εBf = 14.7–25.9%	-	Translucent UV absorption capacity	[276]
Thermoplastic starch	Agave fibers and henquen fibers (0, 10, 20 and 30%wt)	Extrusion and injection molding	-	Ed = 128–454 MPa σme = 11–23 MPa εBf = 10–463%	-	Fire retardant properties	[277]
Thermoplastic starch	Cassava and ahipa peel and bagasse (0.5 and 1.5%wt)	Melt mixing and thermocompression	TDa ⋍ 316 Tmb = 156.5–229.0 Tg1c =  − 43.3–(− 35.8) Tg2c = 43.0–81.8	Ed = 78.2–217.9 MPa σme = 2.6–5.5 MPa εBf = 33.7–76.5%	1.24–1.56 10−10 g/(m s Pa)	Light and UV blocking capacity	[98]
Potato starch	Coffee silverskin (0–10%wt)	Casting	-	Ed = 450–1800 MPa σme = 5–32 MPa εBf = 2–22%	WVTR 49.4–57.9 g/(m2 day)	Increases the films surface hydrophobicity and roughness Antioxidant and UV-protection capacities	[121]
Soy protein isolate	Soybean straw treated and nontreated (0 and 5%wt)	Casting	-	Ed = 298–5527 MPa σme = 4.6–9.0 MPa εBf = 15–35%	9.8–12.8 10−10 g/(m s Pa)	Moisture = 12.8–15.9% Solubility in water = 36–66%	[254]
Soy protein isolate	Waste from red algae Gelidium sesquipedale (Rodophyta) (0–9%wt)	Extrusion and compression molding	TDa > 300	Ed = 75.0–100.2 MPa σme = 4.3–5.9 MPa εBf = 2.1–65.1%	2.29–8.57 10−12 g cm/(cm2 s Pa)	Rough surface with low gloss Greenish and yellowish color of algae waste and soy protein	[250]
Polyhydroxyalkanoates (PHAs)	Fibers of Posidonia oceanica (0–30%wt)	Extrusion and compression molding	TDa = 295–305	Ed = 1.24–3232 MPa σme = 21.88–24.80 MPa εBf = 2.37–6.6.47%	-	Total degradation time < 6 months (in marine sediment)	[116]
Polyhydroxybutyrate (PHB) and polyhydroxyvalerate (PHB-HV)	Agave fibers (10, 20, and 30%wt)	Melt mixing and thermocompression	Tm1b = 135.7–151.7 Tm2b = 148.7–161.8 Tgc = 10.8–17	Ed = 413–770 MPa σme = 13.7–15.7 MPa	-	Good fiber dispersion and compatibility with both matrices Impact strength = 24.5–34.4 J/m	[260]
Poly(β-hydroxybutyrate) /poly(ε-caprolactone)	Cellulosic particles (1%wt)	Melt mixing and injection molding	Tg1c = -53.0 to − 51.5 Tg2c = 17.5–19.7	Ed = 1007.7–1575.0 MPa σme = 24.6–34.9 MPa	-	Incompatibility cellulosic particles-PHB/PCL	[258]
Poly (lactic acid) (PLA)	Banaba fiber (10, 20, and 30%wt)	Injection molding, extrusion + injection molding or extrusion + thermocompression	TDa = 335–337 Tgc = 68–69	Ed = 1400–1650 MPa σme = 15–55 MPa	-	After 20%wt, the tensile strength decreased significantly and the flexural strength of the biocomposite was found to be maximum	[76]
Poly (lactic acid) (PLA)	Seaweed residue after alginate extraction (20, 30, and 40%wt)	Melt mixing and injection molding	TDa = 292–310 Tm1b = 127–149 Tm2b = 142–157 Tgc = 57–61	Ed = 3200–3500 MPa σme = 24.1–47.4 MPa εBf = 0.8–2.0%	-	Composite show lower glow wire flammability index (GWFI) and no dripping of material upon burning, thus showing potential to be used in applications where high temperature occasionally occur	[52]

^aDegradation temperature (T_D); ^bmelting temperature (T_m); ^cglass transition temperature (T_g); ^delastic modulus (E); ^emaximum tensile strength (σ_m); ^felongation at break (ε_B)