Bromo-substituted blocked hexamethylene diisocyanate adduct: synthesis, characterization and application toward polyurethane coating

Jana, Sourita; Ramar, Periyamuthu; Samanta, Debasis; Jaisankar, Sellamuthu N.

doi:10.1080/10601325.2020.1845569

Cited by 6 publications

(18 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[22] Further, alkyl-pyrazole has been studied as blocking agent [23] and polyurethanes have been synthesized from 4bromo-1H-pyrazole-blocked HMDI. [13] polyurethane composites with nanomaterials have been reported by our group recently. [24][25][26][27] Although blocked isocyanates are useful for their non-hazardous methods, the stability and environment-friendliness of polyurethane elastomers depends on the use of aromatic or aliphatic isocyanates and chain extenders like diols, triols, anddiamines.…”

Section: Introductionmentioning

confidence: 93%

“…Among different blocking agents, pyrazole-based blocking agents have attracted special attentions because of their effectiveness in blocking as well as deblocking. [13] The deblocking reactions of pyrazoleblocked isocyanate proceed through five-center complex formation. [12,14] In this context, a group of water-dispersible blocked polyisocyanates were synthesized from toluene 2,4diisocyanate (TDI) and isophorone diisocyanate (IPDI), using ethyl cellosolve (EC), epsilon-caprolactam (CL) and methyl ethyl ketoxime (MEKO) as blocking agents in presence of dimethylol propionic acid.…”

Section: Introductionmentioning

confidence: 99%

“…Figure-2. (A)1 H NMR spectrum of TDI-PPG-1000 (B) 1 H NMR spectrum of TDI-PPG-2000 (C)13 C NMR spectrum of TDI-PEG-400 (D)13 C NMR spectrum of TDI-PPG-2000…”

mentioning

confidence: 99%

“…Before recording compound spectra, the background spectrum was taken. 1 H and13 C NMR spectra has been done with CDCl3 solvent on JEOL 500 MHz ECA instrument at room temperature. For the13 C NMR and DEPT-135, the spectroscopic studies have been done with an operating frequency of 106 MHz.The ppm unit is used to express chemical shift.…”

mentioning

confidence: 99%

“…1 H and13 C NMR spectra has been done with CDCl3 solvent on JEOL 500 MHz ECA instrument at room temperature. For the13 C NMR and DEPT-135, the spectroscopic studies have been done with an operating frequency of 106 MHz.The ppm unit is used to express chemical shift. For thermogravimetric analysis instrument,Netzsch with model name STA 449 F3 jupiter has been used with heating rate 15 ᵒC /min and samples run from 25 ᵒC to 600 ᵒC.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Blocking and Deblocking of Diisocyanate to Synthesize Polyurethanes

Jana¹,

Samanta²,

Fahad³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Diisocyanates, particularly toluene diisocyanate (TDI) are useful for the preparation of various polyurethanes with specific applications as leather-like materials, adhesives, insoles etc. Blocking agents can be used for the operational simplicity and reducing the hazards of TDI. In this paper we reported the use of 3-(4-bromo-phenyl)-1H-pyrazole to block toluene diisocyanate (TDI). FTIR, NMR, thermogravimetric analysis, contact angle and differential scanning calorimetry (DSC) and were used for characterization. Effectiveness of blocking was confirmed by spectroscopic techniques. DSC thermogram shows that blocked adducts deblock at 240 °C causing the regeneration of TDI and blocking agents to react with polyols of different molecular weights forming polyurethanes. The characterization of polyurethanes has been done by Infrared spectroscopy, Nuclear magnetic resonance spectroscopy, thermogravimetric analysis, differential scanning calorimetry and contact angle study.

show abstract

Section: Introductionmentioning

confidence: 93%

Section: Introductionmentioning

confidence: 99%

“…Figure-2. (A)1 H NMR spectrum of TDI-PPG-1000 (B) 1 H NMR spectrum of TDI-PPG-2000 (C)13 C NMR spectrum of TDI-PEG-400 (D)13 C NMR spectrum of TDI-PPG-2000…”

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Blocking and Deblocking of Diisocyanate to Synthesize Polyurethanes

Jana¹,

Samanta²,

Fahad³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

Harnessing leather waste in polymer matrix for sustainable smart shape‐stable phase change materials

Sarkar,

Samanta,

Chaudhuri

et al. 2024

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

The utilization of leather waste (LW) in a polyurethane (PU) matrix makes a smart and novel shape stable phase change material (SSPCM). This is essential for sustainability as it reduces landfill waste after use. The PU is synthesized in bulk with a 90% yield, using biodegradable polycaprolactone diol and bio‐based polyol (castor oil), along with tolylene‐2,4‐diisocyanate. PL and PLG composites are prepared by blending of constituent components PU (P), LW (L), and poly(glycidyl methacrylate) (PGMA, G), as specified by their code names. Role of LW (hydrogen bonding and chemical crosslinking) and morphology are elucidated by FTIR and SEM, respectively. Self‐healing time (2 h), shape fixity ratios (Rf) (PL: 60–80% and PLG: 60–70%) and shape recovery ratios (Rr) (100% for both) are determined at 60°C. PLG displays faster shape recovery in water (<30 s) compared to air (>300 s). Shape stability and thermal properties of the SSPCM are examined using the temperature responsive leakage study, TGA, and DSC. This research introduces a new approach for using leather waste (LW) in SSPCM, with self‐healing and 100% Rr. This material may find application where SSPCM with high durability and flexibility is essential such as textile and footwear materials.

show abstract