Principles of Thermal Degradation

Wypych, George

doi:10.1016/b978-1-927885-61-1.50007-4

Cited by 3 publications

(5 citation statements)

References 342 publications

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“…In phthalate-based plasticizers, thermal stability decreases in the order DTDP > DIDP > DINP > DOP > DIHP > DBP. Thermal degradation is more frequent at temperatures generally more than 200 • C for o-phthalic acid (Moldoveanu, 2019) (e.g., phthalic acid decomposes into phthalic anhydride at 230 • C [Wypych, 2015]). Still, phthalates from more branched alcohol isomers are more susceptible to such degradation because of the tertiary carbon stabilizing the intermediate.…”

Section: Phthalate Stability and Potential For Generation For Noninte...mentioning

confidence: 99%

“…Still, phthalates from more branched alcohol isomers are more susceptible to such degradation because of the tertiary carbon stabilizing the intermediate. Tertiary carbon sites are the susceptible point to initiate radical formation by heat due to the increased stability of intermediates (Wypych, 2015) as hydrogen abstraction is stabilized by the tertiary carbon group (Carraher Jr., 2017). At the industry level, the inclusion of antioxidants can minimize the F I G U R E 2 Thermal degradation of plasticizers (Wypych, 2004).…”

Section: Phthalate Stability and Potential For Generation For Noninte...mentioning

confidence: 99%

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Endocrine modulating chemicals in food packaging: A review of phthalates and bisphenols

Tumu

Vorst

Curtzwiler

2023

Comp Rev Food Sci Food Safe

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Phthalates and bisphenol chemicals have been widely used globally in packaging materials and consumer products for several decades. These highly functional chemicals have become a concern due to their toxicity (i.e., endocrine/hormone modulators) and ability to migrate from food contact materials (FCMs) into food matrices and the environment resulting in human and environmental health risks. FCMs, composed of postconsumer materials, are particularly high risk for containing these compounds. The evaluation of postconsumer recycled feedstocks in FCMs is compulsory and selection of an appropriate detection method to comply with applicable regulations is necessary to evaluate human and environmental safety. Numerous regulations have been proposed and passed globally for both compound classes that are recognized as priority pollutants by the United States Environmental Protection Agency and the European Union. Several brand owners and retailers have also released their own “restricted substance lists” due to the mounting consumer and regulatory concerns. This review article has two goals: (1) discuss the utilization, toxicology, human exposure routes, and occurrence levels of phthalates and bisphenols in FCMs and associated legislation in various countries and (2) discuss critical understanding and updates for detection/quantification techniques. Current techniques discussed include extraction and sample preparation methods (solid‐phase microextraction [SPME], headspace SPME, Soxhlet procedure, ultrasound‐assisted extraction), chromatographic techniques (gas, liquid, detectors), and environmental/blank considerations for quantification. This review complements a previous review of phthalates in foods from 2009 by discussing phthalate and bisphenol characteristics, analytical methods of determining concentrations in packaging materials, and their influence on the migration potential into food.

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Section: Phthalate Stability and Potential For Generation For Noninte...mentioning

confidence: 99%

Section: Phthalate Stability and Potential For Generation For Noninte...mentioning

confidence: 99%

Endocrine modulating chemicals in food packaging: A review of phthalates and bisphenols

Tumu

Vorst

Curtzwiler

2023

Comp Rev Food Sci Food Safe

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“…Meanwhile, the HCl gas released from the PVC pyrolysis acts as a catalyst and further accelerates the degradation. Thus, the zipper autocatalytic dehydrochlorination process of PVC includes the following two steps (Baum et al, 1958;Wypych et al, 2015;Starnes et al, 2004).…”

Section: Thermal Stabilization Mechanismmentioning

confidence: 99%

“…This process is called the zipper autocatalytic dehydrochlorination, which leads to the discoloration and deterioration of mechanical properties of PVC products as a function of time. Particularly, the thermoforming temperature (160-210 °C) of PVC products is much higher than their thermal degradation temperature (about 100 °C), which severely affects the processing and practical application of PVC products (Wypych et al, 2015). Therefore, it is necessary to use special thermal stabilizers to restrain thermal damage due to the high temperatures occurring during the polymer process (Fisch et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Layered double hydroxides as thermal stabilizers for Poly(vinyl chloride): A review

Guo

Leroux

Tian

et al. 2021

Applied Clay Science

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“…Produk-produk akhir PVC dicetak melalui pemanasan pada temperatur 140-190 o C. Kelemahan utama PVC adalah mudah rusak oleh panas, terlebih pada temperatur pencetakan. Proses perusakan PVC oleh panas dinamakan degradasi termal (Wypych, 2015;Yu dkk., 2016). Degradasi termal melepaskan HCl dari struktur polimer PVC dan sekaligus meninggalkan ikatan rangkap.…”

Section: Pendahuluanunclassified

Sintesis Dimerkaptoetil Adipat sebagai Bahan Baku Stabiliser Termal Polivinil Klorida berbasis Timah Organik Ester Balik

Putrawan¹,

Natan²,

Syakuron³

2020

Indo. J. Chem. Res.

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This research aimed to study the synthesis of dimercaptoethyl adipate as raw materials for polyvinyl chloride thermal stabilizer from mercaptoethanol and adipic acid in a batch reactor in which water as a side product was removed by azeotropic evaporation. The study was done through comparative experimental tests where the factors studied included entrainer, mercaptoethanol excess, and reactor volume. It was found that the products obtained were liquid at room condition having clarity in the 95%-99% range, sulfhydryl content in the 23.3%-24.3% range, and yield in the 83.7%-92.1% range. Clarities, sulfhydryl contents, and yields at 20% and 40% mercaptoethanol excesses were not significantly different. At 1 L and 5 L reactor volumes, sulfhydryl contents were found to be significantly different but clarities and yields were not significantly different. Both n-hexane and cyclohexane could be used as entrainers to remove water in the synthesis of dimercaptoethyl adipate. Both entrainers gave clarities and yields that are not significantly different. n-hexane resulted in sulfhydryl content which was 0.77% higher than that of cyclohexane. However, bearing in mind health factors, cyclohexane is considered to be better than n-hexane.

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Principles of Thermal Degradation

Cited by 3 publications

References 342 publications

Endocrine modulating chemicals in food packaging: A review of phthalates and bisphenols

Endocrine modulating chemicals in food packaging: A review of phthalates and bisphenols

Layered double hydroxides as thermal stabilizers for Poly(vinyl chloride): A review

Sintesis Dimerkaptoetil Adipat sebagai Bahan Baku Stabiliser Termal Polivinil Klorida berbasis Timah Organik Ester Balik

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