Chemical, thermal, and mechanical properties and ultraviolet transmittance of novel nano‐hydroxyapatite/polyethylene terephthalate milk bottles

Abstract

Polyethylene terephthalate (PET)/nano‐hydroxyapatite (nHAp) composite granules were obtained using twin‐screw extruder. Preforms were prepared by injection molding and then PET/nHAp bottles were produced by blow molding. For PET bottles with nHAp, the migration amounts of carboxylic acid (COOH), acetaldehyde (AA), diethylene glycol (DEG), and isophthalic acid (IPA); glass transition temperature (Tg); melting temperature (Tm); and the maximum crystallization temperature (Tcry) were measured. The load‐carrying capacity, burst strength, stress cracking, and regional material distribution tests were carried out on the bottles. X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and ultraviolet transmittance analyses were conducted to explain the changes in mechanical, chemical, physical properties, and light transmission of bottles. It was found out that the COOH amount increased and the AA content decreased with increasing nHAp amount. On the other hand, no change was observed in the amounts of DEG and IPA. Although the mechanical properties such as load‐carrying capacity and burst strength of the bottles have improved, it has been determined that the standard environmental stress crack resistance test procedure cannot be applied to such a composite. Experimental findings indicate that nHAp disrupts the chemical structure of PET and it isolates harmful chemicals such as AA by forming intermolecular bonds. Moreover, with the addition of up to 0.8% nHAp, PET bottles block the light transmission approximately 80% within 400–700 nm wave length zone. The study demonstrates that the PET/nHAp composite bottles can be used in the food industry, particularly in the packaging of milk and milk products which are vulnerable to light exposure.

Improvement of environmental stress cracking performance, load‐carrying capacity, and UV light barrier property of polyethylene terephthalate packaging material

“…With the incorporation of 0.8% CaB 2 O 4, the load‐carrying capacity of the PET bottles increased from 86.49 to 180.6 N, an increase of approximately 109%. This may be due to the limitation of PET chain mobility by CaB 2 O 4 and thus increased rigidity 37,43,44 . Demirel et al reached a load‐carrying capacity of 127.5 N for a PET bottle containing 0.8% nano‐hydroxyapatite and observed a similar trend 37 …”

“…This may be due to the limitation of PET chain mobility by CaB 2 O 4 and thus increased rigidity 37,43,44 . Demirel et al reached a load‐carrying capacity of 127.5 N for a PET bottle containing 0.8% nano‐hydroxyapatite and observed a similar trend 37 …”

A way to enhance the mechanical performance and UV visible‐light barrier of polyethylene terephthalate packaging material: Synthesis and application of takedaite (Ca3B2O6)

“…According to the XRD patterns in Figure 3, the peak at approximately 26.6° originates from PET 23,24 . Compared to pure PET, the peak intensity visibly increased with the raise of Ca 3 B 2 O 6 concentration.…”

“…In our previous study, there was no difference in the IPA and DEG degradation of PET in the presence of 0.05%-0.8% (by weight) nanoscale hydroxyapatite. 24…”

Computer Simulation of Polyethylene Terephthalate Carbonated Beverage Bottle Bottom Structure Based on Manual–Automatic Double-Adjustment Optimization

“…In addition, the orientation and crystallinity of PET molecules are also the main factors that determine whether the mechanical properties of finished products are excellent [ 8 , 9 , 10 ]. Demirel et al [ 11 ] used PET/nano hydroxyapatite (nHAp) composite particles to produce PET/nHAp bottles. The PET bottle blocked about 80% light transmission in a wavelength range of 400–700 nm and could be used in the food industry, especially in the packaging of dairy products, which are easily irradiated by light.…”