The use of intermediates obtained from aminoglycolysis of waste poly(ethylene terephthalate) (PET) for the synthesis of water-reducible alkyd resin

2013 ◽  
Vol 91 (5) ◽  
pp. 357-363 ◽  
Author(s):  
Işıl Acar ◽  
Ayça Bal ◽  
Gamze Güçlü

In this study, depolymerization products obtained from an aminoglycolysis reaction of postconsumer poly(ethylene terephthalate) (PET) bottles were used for the synthesis of water-reducible alkyd resins for the first time. We also aimed to reduce the amount of amine using aminoglycolysis products of PET having amine end groups for the neutralization of alkyds in this work. Alkyds formulated to have an oil content of 50% were prepared with glycerine (G), ethylene glycol (EG), fatty acid (FA), and phthalic anhydride (PA) or aminoglycolysis depolymerization products (ADP). The “K alkyd constant system” was used for the formulation calculations of the alkyd resins. The K constant was 1.1 and the ratio of basic equivalents to acid equivalents (R) was 1.15. Physical and chemical film properties and thermal degradation stabilities of these alkyd resins were investigated. According to the results of surface coating tests, the properties of the waste PET-based alkyd resins were found to be compatible with the properties of the reference resins. In addition, thermal degradation stabilities of the water-reducible alkyd resins prepared by ADP were better than that of the reference resin. As a result, we concluded that aminoglycolysis products of waste PET are suitable for manufacturing water-reducible alkyd resins. Furthermore, the amount of amine used for the neutralization stage of preparing water-reducible resin was reduced by 50% using aminoglycolysis products having an amine end group.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Abbas Ahmad Adamu ◽  
Norazilawati Muhamad Sarih ◽  
Seng Neon Gan

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.


2019 ◽  
Vol 10 (39) ◽  
pp. 5324-5332 ◽  
Author(s):  
Sami Zaidi ◽  
Shanmugam Thiyagarajan ◽  
Abdelkader Bougarech ◽  
Fouzia Sebti ◽  
Souhir Abid ◽  
...  

Transparent films of poly(ethylene terephthalate)-co-(ethylene 2,4-furandicarboxylate)s (PET-co-2,4-PEFs) were developed here for the first time, exploring the ability of 2,4-FDCA to impart excellent optical properties to the polymers thereof.


Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 236 ◽  
Author(s):  
Cuong N. Hoang ◽  
Chi T. Pham ◽  
Thu M. Dang ◽  
DongQuy Hoang ◽  
Pyoung-Chan Lee ◽  
...  

Rigid polyurethane foam (PUF) was successfully prepared from a novel oligo-ester-ether-diol obtained from the glycolysis of waste poly(ethylene terephthalate) (PET) bottles via reaction with diethylene glycol (DEG) in the presence of ZnSO4 7H2O. The LC-MS analysis of the oligodiol enabled us to identify 67 chemical homologous structures that were composed of zero to four terephthalate (T) ester units and two to twelve monoethylene glycol (M) ether units. The flame retardant, morphological, compression, and thermal properties of rigid PUFs with and without triphenyl phosphate (TPP) were determined. The Tg values showed that TPP played a role of not only being a flame retardant, but also a plasticizer. PUF with a rather low TPP loading had an excellent flame retardancy and high thermal stability. A loading of 10 wt % TPP not only achieved a UL-94 V-0 rating, but also obtained an LOI value of 21%. Meanwhile, the PUF without a flame retardant did not achieve a UL-94 HB rating; the sample completely burned to the holder clamp and yielded a low LOI value (17%). The fire properties measured with the cone calorimeter were also discussed, and the results further proved that the flame retardancy of the PUF with the addition of TPP was improved significantly. The polymeric material meets the demands of density and compression strength for commercial PUF, as well as the needs of environmental development. The current study may help overcome the drawback of intrinsic high flammability and enlarge the fire safety applications of materials with a high percentage of recycled PET.


2020 ◽  
Vol 10 (3) ◽  
pp. 1046 ◽  
Author(s):  
Nicolas Descamps ◽  
Florian Fernandez ◽  
Pierre Heijboer ◽  
René Saint-Loup ◽  
Nicolas Jacquel

Poly(ethylene-co-isosorbide terephthalate) (PEIT) copolyesters could be used in various applications depending on their ability to crystallize. Moreover, the possibility to carry out solid-state post-condensation (SSP) is conditioned by its ability to sufficiently crystallize. The present study, thus, gives a systematic investigation of isothermal crystallization of these statistical copolyesters with isosorbide contents ranging from 4.8 to 20.8 mol.%. For each copolyester composition, the lowest isothermal half crystallization times and the highest Avrami constant (K) were obtained around 170 °C. Over the range of composition that was studied, both melting points and melting enthalpies decreased with increasing amounts of isosorbide (from 250 to 207 °C and from 55 to 28 J/g, respectively). On the contrary, half crystallization time displayed an exponential increase when increasing isosorbide contents in the studied range. Finally, structural and thermal analysis of PIT homopolyester are reported for the first time, showing that only ET moieties crystallized when PEIT was subjected to isothermal crystallization at 170 °C.


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