Thermal degradation of MDI-based segmented polyurethanes

Shieh, Yeong‐Tarng; Chen, Hui-Tzu; Liu, Kuan-Han; Twu, Yawo-Kuo

doi:10.1002/(sici)1099-0518(19991115)37:22<4126::aid-pola11>3.0.co;2-a

Cited by 54 publications

(27 citation statements)

References 12 publications

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“…The thermal stability of the prepared PUR elastomers were characterized by the initial decomposition temperature (from TGA), maximum rate of decomposition (from DTG) and weight loss at 600 C (from TGA). The PURs show reduced thermostability and their thermal stability is dependent on the chemical structure of the polyols and diisocyanates used in their preparation [2][3][4][5]. Both steps of degradation using the Freeman-Carroll method were studied.…”

mentioning

confidence: 60%

Thermal Degradation of Polyurethane Elastomers: Determination of Kinetic Parameters

Bajsić

Rek

Agić

2003

Journal of Elastomers & Plastics

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The objective of this study is determining the kinetic parameters of thermal degradation of polyurethane elastomers before and after UV irradiation. To determine the kinetic parameters of elastomeric polyurethane (PUR) decomposition the Freeman-Carroll method of calculation is applied. The effect of soft segment and hard segment type, soft segment molecular weight and hard segment content on the kinetic parameters of the degradation process were measured. Polyurethane elastomers were obtained from poly(oxytetramethylene) glycol, PTMO, of 1000 and 2000 molecular weight and polycaprolactone glycol of 1250 molecular weight (PCL), 4,4 0 diphenylmethan diisocyanate (MDI) and 4,4 0 -dicyclohexylmethane diisocyanate (H 12 MDI) and 1,4-butanediol as chain extender. The activation energy values obtained for PUR elastomers based on polyester soft segment were higher than those based on polyether soft segment.The PUR elastomers based on aromatic type of diisocyanate have lower activation energy values than those based on cycloaliphatic type of diisocyanate.

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mentioning

confidence: 60%

Thermal Degradation of Polyurethane Elastomers: Determination of Kinetic Parameters

Bajsić

Rek

Agić

2003

Journal of Elastomers & Plastics

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“…The hard micro-domain achieve the necessary mobility to reorganize into bigger domains and the shorter HS is allowed to dissolve in the soft phase, which consequently causing the increasing of the T g [95]. The same observations about ageing and processing conditions that influence the microstructure of the polymer are well-known and documented in the literature [3,72,96,97,[102][103][104].…”

Section: Thermal Propertiesmentioning

confidence: 85%

Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review

Datta

Kasprzyk

2017

Polymer Engineering & Sci

115

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Thermoplastic polyurethanes (TPUs) materials are obtained by the reaction of polyol (ether-, ester-, and carbonate-based diols with average molecular weight in the range from 1,000 to 3,000 g/mol) with aliphatic or aromatic diisocyanates. Synthesized materials consist of the hard and soft segments which are separated in different level. All mechanical and thermal properties of TPUs depend on the chemical structure of used monomers, volume fraction, and interaction between the hard and soft segments. Presented work is the review of the synthesis and the structure-properties relationship analysis in the case of TPU. The most popular reactants used for the production of the TPUs have petrochemical-based origin.

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“…[2][3][4] Many authors have investigated ageing of TPU under UV radiation, elevated temperatures, different atmospheres (air, nitrogen, ozone), humidity, electron beam irradiation or combinations thereof using different mechanical characterization methods such as Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Nuclear Magnetic Resonance spectroscopy (NMR spectroscopy), UV/Vis/NIR spectroscopy, and Fourier Transform Infrared (FTIR) or Attenuated Total Reflectance (ATR) spectroscopy. [2][3][4][5][6][7][8][9][10][11][12][13] Changes in molecular and supramolecular structure and in mechanical and optical properties were observed. Thompson et al reported decrease in molecular weight after hydrolytic ageing of TPU.…”

Section: Introductionmentioning

confidence: 99%

“…[4] Rosu et al, Wilhelm and Gardette and other authors reported significant yellowing of TPU after exposure to UV radiation or heat. [18,19,3,7] Nevertheless, degradation mechanisms in TPU have not been fully understood yet. Due to the high chemical diversity in composition of TPU and complex interrelationships with environment (e.g.…”

Section: Introductionmentioning

confidence: 99%

Investigation of Ageing Mechanisms in Thermoplastic Polyurethanes by Means of IR and Raman Spectroscopy

Bruckmoser

Resch

2014

Macromolecular Symposia

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Summary: Within the present study FTIR and Raman spectroscopy are evaluated as to specific strengths in terms of analysing deterioration in TPU induced by UV radiation or thermal load. A conventional ester based TPU grade formulated from 4,4'-methylene diphenyl diisocyanate, 1,4-butanediol and polycaprolactone was investigated. Exposure to UV was done in a Suntest CPSþ at different exposure times. Thermal treatment was done in an air circulation oven at 180 C and different exposure times. Exposed samples were characterized as to changes in molecular structure with complementary methods ATR and Raman spectroscopy. To establish interrelationships between structural changes and macroscopic material characteristics UV/Vis/NIR spectroscopy and DSC were applied.UV/Vis/NIR spectroscopy clearly indicated yellowing, and thus an increase in absorption in the visible wavelength range, of TPU after exposure to UV or to thermal load. Yellowing correlated well with formation of chromophoric groups detected by ATR and Raman spectroscopy. ATR spectroscopy turned out to be very sensitive in detection of changes in chemical structure induced by UV radiation. Raman spectroscopy was found to be very sensitive in detection of changes in chemical structure induced by thermal load. No distinct effect of UV exposure on morphology of TPU was ascertained. In contrast, a strong effect of thermal treatment on (para)crystalline morphology was observed.

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Thermal degradation of MDI-based segmented polyurethanes

Cited by 54 publications

References 12 publications

Thermal Degradation of Polyurethane Elastomers: Determination of Kinetic Parameters

Thermal Degradation of Polyurethane Elastomers: Determination of Kinetic Parameters

Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review

Investigation of Ageing Mechanisms in Thermoplastic Polyurethanes by Means of IR and Raman Spectroscopy

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