Crazing Effect on the Bio-Based Conducting Polymer Film

Abstract

The biodegradability problem of polymer waste is one of the fatal pollutFions to the environment. Enzymes play an essential role in increasing the biodegradability of polymers. In a previous study, antistatic polymer film based on poly(lactic acid) (PLA) as a matrix and polyaniline (PAni) as a conductive filler, was prepared. To solve the problem of polymer wastes pollution, a crazing technique was applied to the prepared polymer film (PLA/PAni) to enhance the action of enzymes in the biodegradation of polymer. This research studied the biodegradation test based on crazed and non-crazed PLA/PAni films by enzymes. The presence of crazes in PLA/PAni film was evaluated using an optical microscope and scanning electron microscopy (SEM). The optical microscope displayed the crazed in the lamellae form, while the SEM image revealed microcracks in the fibrils form. Meanwhile, the tensile strength of the crazed PLA/PAni film was recorded as 19.25 MPa, which is almost comparable to the original PLA/PAni film with a tensile strength of 20.02 MPa. However, the Young modulus decreased progressively from 1113 MPa for PLA/PAni to 651 MPa for crazed PLA/PAni film, while the tensile strain increased 150% after crazing. The significant decrement in the Young modulus and increment in the tensile strain was due to the craze propagation. The entanglement was reduced and the chain mobility along the polymer chain increased, thus leading to lower resistance to deformation of the polymer chain and becoming more flexible. The presence of crazes in PLA/PAni film showed a substantial change in weight loss with increasing the time of degradation. The weight loss of crazed PLA/PAni film increased to 42%, higher than that of non-crazed PLA/PAni film with only 31%. The nucleation of crazes increases the fragmentation and depolymerization of PLA/PAni film that induced microbial attack and led to higher weight loss. In conclusion, the presence of crazes in PLA/PAni film significantly improved enzymes’ action, speeding up the polymer film’s biodegradability.

Characterization and quantification of oxidative stress induced particle debris from polypropylene surgical mesh

“…Mesh implantation within an oxidative stress environment, in this study H 2 O 2 , further promotes an increase in surface crazing through exposure to oxidative degradation processes. The formation of crazes not only acts as a precursor to larger structural surface cracking, which are expected to affect the mesh material's mechanical properties, [ 31 ] but also can act as a pathway for bulk polymer oxidation. Eventually, surface cracking propagates and exposes greater surface areas thereby making more material available for further degradation.…”

Emerging Applications of Versatile Polyaniline-Based Polymers in the Food Industry

“…PANI is able to improve upon the chemical and mechanical properties of biopolymers so that they can be more feasible for applications in food packaging [ 64 , 65 , 66 ]. At the same time, studies have shown that biopolymer matrices retain their biodegradability behaviour after the incorporation of PANI [ 29 , 67 , 68 , 69 ]. In fact, the addition of PANI improves the biodegradability of low-density polyethylene film (LDPE) via oxo-biodegradation [ 70 ].…”

Special Issue “Mechanical Performance of Sustainable Bio-Based Compounds”

“…The purpose of this Special Issue was to collect original contributions, both research papers and reviews, showing recent results and/or positive advances in the behavior of new sustainable biomaterials under applied mechanical stress, in both static and dynamic modes, and evaluating the characteristics of resistance, moduli and/or viscoelasticity in view of potential applications in biotechnology and biomedicine [4], tissue engineering [5], medical devices [6,7], surgical or dental implants [8], agriculture [9], packaging [3,10,11], textiles [1], automotives [12][13][14], green buildings and construction [15], radiation dosimetry [16], and 3D printing [17][18][19].…”

“…Hernandez et al investigated the effects of microspheres, carbon fibers, or polyethylene glycol added to polyhydroxybutyrate (PHB) resin on the thermal and mechanical properties of the final compounds [21]. A polymer film based on poly(lactic acid) (PLA) as a matrix and polyaniline (PAni) as a conductive filler was prepared by Wong et al [10], to obtain antistatic properties. Polyaniline was chosen due to to its good biocompatibility and conductivity and excellent performance in combination with a PLA matrix.…”