Reatarding effect of nitrogen ylide for the polymerization of N-vinyl pyrrolidone

Vasishtha, Rita; Kumar, P.; Awasthi, Seema; Bhatnagar, Urvi; Srivastava, A. K.

doi:10.1007/bf01410406

Cited by 9 publications

(6 citation statements)

References 11 publications

(9 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ylides are very versatile in their behavior. They act as retarders,8 initiators9 and degradative chain transfer agents10 in the polymerization of vinyl monomers. The application of ylides containing N,10 Sb,11 As9 and S12 in the domain of polymer science is a current topic of interest, with a history of 20 years.…”

Section: Introductionmentioning

confidence: 99%

Analysis of imidacloprid residues in fruits, vegetables, cereals, fruit juices, and baby foods, and daily intake estimation in and around Lucknow, India

Kapoor¹,

Srivastava²,

Srivastava³

et al. 2013

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

Abstract-A total of 250 samples-including fruits, fruit juices, and baby foods (50 samples each), vegetables (70 samples), and cereals (30 samples)-were collected from Lucknow, India, and analyzed for the presence of imidacloprid residues. The QuEChERS (quick, easy, cheap, effective, rugged, and safe) method of extraction coupled with high-performance liquid chromatographic analysis were carried out, and imidacloprid residues were qualitatively confirmed by liquid chromatography-mass spectrometry. Imidacloprid was not detected in samples of fruit juices and baby foods. It was, however, detected in 38 samples of fruits, vegetables, and cereals, which is about 15.20% of the total samples. Of samples of fruits, 22% showed the presence of imidacloprid, and 2% of samples showed residues above the maximal residue limit. Although imidacloprid was detected in 24% of vegetable samples, only 5.71% showed the presence of imidacloprid above the maximal residue limit. However, 33% of cereal samples showed the presence of imidacloprid, and about 3% of samples were above the maximal residue limit. The calculated estimated daily intake ranged between 0.004 and 0.131 mg/kg body weight, and the hazard indices ranged from 0.007 to 0.218 for these food commodities. It is therefore indicated that lifetime consumption of vegetables, fruits, fruit juices, baby foods, wheat, rice, and pulses may not pose a health hazard for the population of Lucknow because the hazard indices for imidacloprid residues were below one. Environ. Toxicol. Chem. 2013;32:723-727. # 2012 SETAC

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of imidacloprid residues in fruits, vegetables, cereals, fruit juices, and baby foods, and daily intake estimation in and around Lucknow, India

Kapoor¹,

Srivastava²,

Srivastava³

et al. 2013

Enviro Toxic and Chemistry

View full text Add to dashboard Cite

show abstract

“…The R p , a direct function of temperature and the apparent energy of activation, determined from the slope of the Arrhenius plot, is 33 kJ/mol (Fig. 6), which matches with the value given in the literature [17]. …”

Section: Effect Of Temperaturementioning

confidence: 74%

“…A search of the literature reveals that benzoyl peroxide [14], azobisisobutyronitrile [14,15], 60 Co γ -radiation [15] and cumene hydroperoxide [16] have been used as an initiator for the polymerization of N-vinyl pyrrolidone (N-VP). However, no ylide has been used as an initiator for the polymerization of N-VP, although N [17] and S [18] ylides have been used as chain-transfer agent in the presence of azobisisobutyronitrile as an initiator for the polymerization of N-VP.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of poly(N-vinyl pyrrolidone) initiated by stibonium ylide

Srivastava¹,

Srivastava²

2006

Designed Monomers and Polymers

Self Cite

View full text Add to dashboard Cite

1,2,3,4-Tetraphenylcyclopentadiene triphenyl stibonium ylide initiated radical polymerization of N-vinyl pyrrolidone (N-VP) in dioxane, at 60±0.2 • C, for 60 min under nitrogen atmosphere has been carried out. The system follows ideal kinetics, i.e., R p ∝ [ylide] 0.5 [N-VP] 1.0 . The values of k 2 p /k t and overall energy of activation have been computed as 0.5 × 10 −2 l mol −1 s −1 and 33 kJ/mol, respectively. The FT-IR spectrum shows a band at 1692 cm −1 due to the C O group of N-vinyl pyrrolidone. The 1 H-NMR spectrum shows multiplet at 2.4 δ ppm and a doublet at 3.7 δ ppm due to CH 2 protons. The DSC curve shows a glass transition temperature (T g ) as 48 • C.The presence of six hyperfine lines in the ESR spectrum indicates that the system follows free radical polymerization and the initiation is brought about by phenyl radical.

show abstract

“…Ylides, i.e., 1,2-dipolar compounds having the general formula C X , where X may be phosphorus, sulphur, arsenicum, antimony and nitrogen, bismuth, etc., have been well established as initiators [10], retarders [11] and degredative chain-transfer agents [12] in polymerization of different vinyl monomers yielding homo-, co-and terpolymer, but the application of ylides as novel radical initiator for synthesis of IPNs is still scarce [9].…”

Section: Introductionmentioning

confidence: 99%

Terpene-based semi-interpenetrating polymer networks initiated by p-nitrobenzyl triphenyl phosphonium ylide: synthesis and characterization

Prajapati¹,

Varshney²

2006

Designed Monomers and Polymers

View full text Add to dashboard Cite

A series of semi-interpenetrating polymer networks (IPNs) based on poly(α-terpineol-costyrene) and ethylacrylate cross-linked with divinyl benzene have been synthesized at 80 • C for 80 min in dioxane, initiated by p-nitrobenzyl triphenyl phosphonium ylide, under an inert atmosphere of nitrogen. The Fourier transform infrared spectrum attributes structural evidences for IPNs, indicating characteristic frequencies of the ester group of ethyl acrylate at 1727 cm −1 and alcoholic group of α-terpineol at 3390 cm −1 . The percentage swelling and average molecular weight between crosslinks (m c ) are a direct function of α-terpineol-co-styrene and p-nitrobenzyl triphenyl phosphonium ylide and inverse function of ethyl acrylate and divinylbenzene. The semi-IPN system is confirmed by two T g values from the differential scanning calorimetry scan at 15 and 59 • C. SEM micrographs show phase separation. The thermogravimetric analysis (TGA) curve shows the IPN to be thermally stable. From the TGA curve the activation energy is calculated using the Coats and Redfern equation to be 23 kJ/mol.

show abstract

Reatarding effect of nitrogen ylide for the polymerization of N-vinyl pyrrolidone

Cited by 9 publications

References 11 publications

Analysis of imidacloprid residues in fruits, vegetables, cereals, fruit juices, and baby foods, and daily intake estimation in and around Lucknow, India

Analysis of imidacloprid residues in fruits, vegetables, cereals, fruit juices, and baby foods, and daily intake estimation in and around Lucknow, India

Synthesis and characterization of poly(N-vinyl pyrrolidone) initiated by stibonium ylide

Terpene-based semi-interpenetrating polymer networks initiated by p-nitrobenzyl triphenyl phosphonium ylide: synthesis and characterization

Contact Info

Product

Resources

About