Flame retardant properties of triazine phosphonates derivative with cotton fabric

The flame retardant behavior of cotton fabric treated with phosphorus-nitrogen containing triazine compound was evaluated. It was found that cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) is an excellent starting material for the preparation of phosphonate flame retardants that interact well with cotton to improve flame resistance (FR) performance. Tetraethyl 6-chloro-1,3,5-triazine-2,4-diyldiphosphonate (TECTDP) has been prepared by a simple one-step reaction in high yield (98.0 %). Cotton fabrics treated with TECTDP result in covalent bond formation between TECTDP and hydroxyl groups in cotton fabrics. This FR system provides an efficient flame retardant for cotton textiles at low cost to meet government mandates. In this study, the FR material was synthesized and characterized by ¹H and ¹³C nuclear magnetic resonance (NMR), and LC-MS spectroscopy. The chemical structure of cotton twill fabric treated with TECTDP by pad-dry-cure method was analyzed by FT-MIR and SEM. Furthermore, the thermal and flammability properties were evaluated by thermogravimetric analysis (TGA), limiting oxygen index (LOI, ASTM D-2863-09), and a vertical flame test (ASTM D-6413-08).     

Analysis of 2‐Acetyl‐1‐Pyrroline in Rice by HSSE/GC/MS

An extremely sensitive method for the analysis of 2‐acetyl‐1‐pyrroline (2AP) in rice, employing stir bar sorptive extraction (Twister) was studied. The Twister stir bar is placed in the headspace of a 20‐mL vial containing 1 g of rice kernels, 7.5 mL of 0.1M KOH, and 2.2 g of NaCl, along with a second Teflon‐coated stir bar for mixing. Analytes are adsorbed onto the Twister for 4 hr at 40°C and then desorbed at 270°C into a GC column while cryofocusing at –80°C. The headspace sorptive extraction (HSSE) method was able to detect <0.1 ppb of 2AP in rice. The precision of the HSSE method (>10%) was not as good as the GC/FID method (≈6%). Using HSSE, 2AP was observed in all samples generally considered to be aromatic and was not observed in any nonaromatic samples. Additionally, a modified method for the synthesis of 2‐acetyl‐1‐pyrroline was studied and the presence of a tautomer of 2‐acetyl‐1‐pyrroline was confirmed.     

Effects of plastic mulch, sowing date and cultivar on the yield and maturity of forage maize grown under marginal climatic conditions in Northern Ireland

The effects of growing forage maize (Zea mays) with or without plastic mulching treatments on the dry‐matter (DM) yield, cob yield, DM content and starch content was investigated in Northern Ireland in 1996 and 1997. Cultivars differing in maturity characteristics were sown in spring at a range of dates in three replicated plot experiments and were used to compare the effects of two plastic mulches and an untreated control: one plastic mulch completely covered the rows (floating); the other had holes punched in the plastic, through which the plants grew (punch). Between April and October in 1996 and 1997, the Ontario heat units (OU) received were above average at 2489 and 2660 respectively; in those years without plastic mulches, the earliest maturing cultivar, Melody, yielded 11·0 and 13·6 t DM ha^–1, with dry‐matter contents of 214 and 215 g kg^–1 respectively. Mean daily increases in soil and air temperature under plastic mulches of up to 6°C and 11°C, respectively, were closely related to solar radiation. Under plastic mulches, 15% fewer OU were required to reach silking, and 33% more OU were available between silking and harvest. Meaned over three experiments, two years and three cultivars, plastic mulches, when compared with the unmulched control, increased maize yield from 12·0 to 14·7 t DM ha^–1, cob yield from 3·7 to 6·8 t DM ha^–1, dry‐matter content from 230 to 270 g kg^–1 and starch content from 198 to 272 g kg^–1. The effect of plastic mulch on the maturation of the crop was greatest at earlier sowings. In 1997, plants from an early sowing date (10 April) that had recently emerged through the punch plastic mulch were damaged by frost, whereas those in the floating plastic mulch plots were unaffected. When the floating plastic mulch was left on after the six‐ to eight‐leaf stage of the first‐early maize cultivar Hudson, the plants were physically damaged and the yield reduced, but DM and starch contents continued to increase. The increases in yield and dry‐matter content under the plastic mulch were greater in Diamant (second‐early cultivar) than in Melody (first‐early cultivar). It was concluded that, under marginal climatic conditions, plastic mulches ought to be used to improve the reliability of early cultivars rather than growing later maturing cultivars.