scholarly journals New UV Curable Acrylated Urethane-Oligoesters Derived From Poly(Ethylene Terephthalate) PET Waste

2021 ◽  
Author(s):  
Medhat S. Farahat Khedr
Keyword(s):  
Ethylene Terephthalate ◽  
Value Added ◽  
Hydroxyl Groups ◽  
Polymer Waste ◽  
Uv Curable ◽  
Pet Waste ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
High Mechanical Stress ◽  
Value Added Products

Abstract The glycolysis products of polyethylene terephthalate (PET) waste represent a potential source for many value-added products that contain terephthalate repeating units in their backbones. Terephthalate repeating units were not attained directly from terephthalic acid due to its high melting point in addition to its tendency to sublime before it reacts. Glycolysis of PET provides an excellent solution for recycling polymer waste and constitutes a substantial starting material for manufacturing materials with high mechanical stress, such as unsaturated polyesters and polyurethane products. In this study, PET was first depolymerized by glycolysis, and glycolyzed products were then dimerized by reaction with toluene di-isocyanate TDI with half equivalence of their hydroxyl groups for the purpose of inserting urethane blocks into the oligomer structure. The remaining half equivalence of terminal hydroxyl groups was modified into acrylate groups by an acrylation reaction. The acrylated oligo urethane ester products were crosslinked with different co-monomers and tested for UV curability and mechanical properties, and they showed outstanding results.

Polyurethane resin derived from polyol of palm olein and recycled poly(ethylene terephthalate)

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Abbas Ahmad Adamu ◽  
Norazilawati Muhamad Sarih ◽  
Seng Neon Gan
Keyword(s):  
Thermal Stability ◽  
Palm Olein ◽  
Ethylene Terephthalate ◽  
Alkali Resistance ◽  
Pet Waste ◽  
Content Type ◽  
Pet Bottles ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Excellent Adhesion

Purpose Poly(ethylene terephthalate) (PET) waste from soft drink bottles was incorporated into palm olein alkyd to produce new polyol for use in polyurethane resins as surface protection on metal surfaces. Design/methodology/approach Alkyd was prepared from palm olein, glycerol and phthalic anhydride. PET underwent simultaneous glycolysis and transesterification reactions with the alkyd. Varying the amount of PET has led to polyols with different viscosities. Polyurethane resins were produced by reacting the polyols with toluene diisocyanate. The resins were coated on mild steel panels and cured. Performances of the cured films were tested. Findings The polyurethanes (PU) resin cured to a harder film with better thermal stability. Films showed excellent adhesion properties, while higher content of PET exhibited higher pencil hardness, better water, salt, acid and alkali resistance. Research limitations/implications Other vegetable oils could also be used. The alkyd structure could be changed by formulation to have different functionality and the ability to incorporate higher amount of PET waste. Rate of glycolysis of PET could be increased by higher amount of ethylene glycol. Practical implications This method has managed to use waste PET in producing new polyol and PU resins. The cured films exhibit good mechanical and chemical properties, as well as excellent adhesion and thermal stability. Social implications The non-biodegradable PET has created environmental pollution problems connected to littering and illegal landfilling. It has become necessary to pay greater attention to recycling PET bottles for obtaining valuable products. Originality/value This approach is different from the earlier reports, where PET was recycled to recover the raw materials.

scholarly journals Chemical Upcycling of PET Waste towards Terephthalate Redox Nanoparticles for Energy Storage

2021 ◽  
Vol 2 (4) ◽  
pp. 610-621
Author(s):  
Nicolas Goujon ◽  
Jérémy Demarteau ◽  
Xabier Lopez de Pariza ◽  
Nerea Casado ◽  
Haritz Sardon ◽  
...  
Keyword(s):  
Energy Storage ◽  
Ethylene Terephthalate ◽  
Pet Waste ◽  
Pet Bottles ◽  
Redox Active ◽  
Poly Ethylene Terephthalate ◽  
Standard Redox Potential ◽  
Active Nanoparticles ◽  
Specific Discharge ◽  
Poly Ethylene

Over 30 million ton of poly(ethylene terephthalate) (PET) is produced each year and no more than 60% of all PET bottles are reclaimed for recycling due to material property deteriorations during the mechanical recycling process. Herein, a sustainable approach is proposed to produce redox-active nanoparticles via the chemical upcycling of poly(ethylene terephthalate) (PET) waste for application in energy storage. Redox-active nanoparticles of sizes lower than 100 nm were prepared by emulsion polymerization of a methacrylic-terephthalate monomer obtained by a simple methacrylate functionalization of the depolymerization product of PET (i.e., bis-hydroxy(2-ethyl) terephthalate, BHET). The initial cyclic voltammetry results of the depolymerization product of PET used as a model compound show a reversible redox process, when using a 0.1 M tetrabutylammonium hexafluorophosphate/dimethyl sulfoxide electrolyte system, with a standard redox potential of −2.12 V vs. Fc/Fc+. Finally, the cycling performance of terephthalate nanoparticles was investigated using a 0.1 M TBAPF6 solution in acetonitrile as electrolyte in a three-electrode cell. The terephthalate anode electrode displays good cycling stability and performance at high C-rate (i.e., ≥5C), delivering a stable specific discharge capacity of 32.8 mAh.g−1 at a C-rate of 30 C, with a capacity retention of 94% after 100 cycles. However, a large hysteresis between the specific discharge and charge capacities and capacity fading are observed at lower C-rate (i.e., ≤2C), suggesting some irreversibility of redox reactions associated with the terephthalate moiety, in particular related to the oxidation process.

scholarly journals Metal-Containing Ionic Liquids: Highly Effective Catalysts for Degradation of Poly(Ethylene Terephthalate)

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Qun Feng Yue ◽  
Hua Guang Yang ◽  
Mi Lin Zhang ◽  
Xue Feng Bai
Keyword(s):  
Ionic Liquids ◽  
Ethylene Glycol ◽  
Qualitative Analysis ◽  
Reaction Temperature ◽  
Ethylene Terephthalate ◽  
Main Product ◽  
Local Market ◽  
Pet Waste ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Poly(ethylene terephthalate) (PET) waste from local market was depolymerized by ethylene glycol (EG) in the presence of metal-containing ionic liquids, and the qualitative analysis showed that the bis(hydroxyethyl) terephthalate (BHET) was the main product in this process. Compared with other metal-containing ionic liquids, [Bmim]ZnCl3was considered the best catalyst in the glycolysis of PET. When the reaction temperature was 180°C, the conversion of PET reached 97.9% and the BHET was yielded to 83.3% within 5 h. At the same time, [Bmim]ZnCl3could be reused for six times without obvious decrease in the yield of BHET. Additional, the effects of waste PET’s source and size were investigated.

scholarly journals Crystallization and Thermal Behaviors of Poly(ethylene terephthalate)/Bisphenols Complexes through Melt Post-Polycondensation

Polymers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3053
Author(s):  
Shichang Chen ◽  
Shangdong Xie ◽  
Shanshan Guang ◽  
Jianna Bao ◽  
Xianming Zhang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Crystallization Kinetics ◽  
Ethylene Terephthalate ◽  
Crystallization Rate ◽  
Chain Growth ◽  
Hydroxyl Groups ◽  
Lamellar Thickness ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene ◽  
Thermal Stability Of

Three kinds of modified poly(ethylene terephthalate) (PET) were prepared by solution blending combined with melt post-polycondensation, using 4,4′-thiodiphenol (TDP), 4,4′-oxydiphenol (ODP) and hydroquinone (HQ) as the bisphenols, respectively. The effects of TDP, ODP and HQ on melt post-polycondensation process and crystallization kinetics, melting behaviors, crystallinity and thermal stability of PET/bisphenols complexes were investigated in detail. Excellent chain growth of PET could be achieved by addition of 1 wt% bisphenols, but intrinsic viscosity of modified PET decreased with further bisphenols content. Intermolecular hydrogen bonding between carbonyl groups of PET and hydroxyl groups of bisphenols were verified by Fourier transform infrared spectroscopy. Compare to pure PET, both the crystallization rate and melting temperatures of PET/bisphenols complexes were reduced obviously, suggesting an impeded crystallization and reduced lamellar thickness. Moreover, the structural difference between TDP, ODP and HQ played an important role on crystallization kinetics. It was proposed that the crystallization rate of TDP modified PET was reduced significantly due to the larger amount of rigid benzene ring and larger polarity than that of PET with ODP or HQ. X-ray diffraction results showed that the crystalline structure of PET did not change from the incorporation of bisphenols, but crystallinity of PET decreased with increasing bisphenols content. Thermal stability of modified PET declined slightly, which was hardly affected by the molecular structure of bisphenols.

Polyester derived from recycled poly(ethylene terephthalate) waste for regenerative medicine

RSC Advances ◽  
2014 ◽  
Vol 4 (102) ◽  
pp. 58805-58815 ◽  
Author(s):  
Kishor Sarkar ◽  
Sai Rama Krishna Meka ◽  
Amrit Bagchi ◽  
N. S. Krishna ◽  
S. G. Ramachandra ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Regenerative Medicine ◽  
Ethylene Terephthalate ◽  
3D Scaffold ◽  
Pet Waste ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Fabrication of 3D scaffold from PET waste for tissue engineering.

Sign in / Sign up

Export Citation Format

Share Document