Characterization of biofilms developed from alginate extracted from Padina sp. incorporated with calcium chloride (CaCl₂)

Abstract

Seaweed has been used in many industries, whether directly or its extract. Padina sp. is one of the understudied species of brown seaweed. Brown seaweed have alginate embedded in their cell wall which is a type of hydrocolloids and can be used in many industries and applications including development of biofilms. The main objective of this current study is to develop biofilms using alginate extracted from Padina sp. and incorporated with calcium chloride at different concentrations. Prior to that, the functional groups of Padina sp. and alginate extract were determined. Then, functional groups, surface morphology, mechanical properties, swelling ability and biodegradability of the biofilms were studied using standard methods. The results showed that there were no significant changes in their FTIR spectra with increasing CaCl2 content. Surface morphology showed improvement in bonding while mechanical properties showed the best tensile strength of 9.43mm and 8.61mm elongation-at-break (EAB) after addition of 0.12g CaCl2. As for their swelling and biodegradability, the samples were completely dissolved after one hour and degraded after 24 hours. This shows that the biofilms with CaCl2 indeed improve the quality of alginate-based biofilms which can further be studied to improve other aspects such as water sorption kinetic and thermal stability.

Modified Sodium Alginate for Degradable Supramolecular Plastic with High Mechanical Strength

“…The maximum breaking strength is 26.5 MPa, which is much higher than those reported in the literature (Tables S1). [9][10][11]16,28,31] The breaking strain is 3.6 times of that of the pristine SA film and is comparable to those of the modified sodium alginate film reported previously (Table S2). Moreover, the Young's modulus and the strength at break are 10 MPa and 26.5 MPa, respectively.…”

“…The optimal SA to PEG ratio is 4 : 1 at which the mechanical strength of SA/PEG/FeCl 3 reaches the maximum. The maximum breaking strength is 26.5 MPa, which is much higher than those reported in the literature (Tables S1) [9–11,16,28,31] . The breaking strain is 3.6 times of that of the pristine SA film and is comparable to those of the modified sodium alginate film reported previously (Table S2).…”

“…Because of the abundance in nature, easy availability and good degradability, [9][10][11][12][13] sodium alginate is considered as a promising candidate for bioplastic. [14][15][16][17][18][19] In recent years, researches on sodium alginate-based bioplastics have been focused on the addition of various additives (such as cellulose, [20] multi-walled carbon nanotubes [21] ) which may help to improve their mechanical properties or the surface modification (using hydrophobic dodecyltrimethoxysilane, [22] dodecyl glycidyl ether, [23] silica nanoparticles [24] or methyl trimethoxysilane [25] ) which aims to increase its hydrophobicity. In addition, specific molecules have been grafted onto the sodium alginate molecular chain, such as β-carboxyethyl acrylate, acrylamide and ɛ-polylysine, ultimately conferring the sodium alginate with antimicrobial properties.…”

Characterization of bioplastics developed from Kappaphycus alvarezii crosslinked with commercial sodium alginate

“…It was concluded that both K. alvarezii-and alginate-based films individually each have their own pros and cons. Hanry et al (2022) and Hanry & Surugau (2020) studies revealed that there was more room for the use of K. alvarezii-and alginate-based bioplastics with the goal of replacing single-use packaging. This study is a follow-up that aims to serve as a baseline reference for following research by comparing each characteristic to assess the effects of combining commercial sodium alginate with K. alvarezii at various ratios to produce seaweedbased bioplastics.…”