“Flame retardancy for thermoplastics is a challenging task


“Flame retardancy for thermoplastics is a challenging task where chemists and engineers work together to find solutions to improve the burning behavior

without strongly influencing other key properties IAP inhibitor of the material. In this work, the halogen-free additives aluminum diethylphosphinate (AlPi-Et) and a mixture of aluminum phosphinate (AlPi) and resorcinol-bis(di-2,6-xylyl phosphate) (AlPi-H + RXP) are employed in neat and reinforced poly(butylene terephthalate) (PBT), and the morphology, mechanical performance, rheological behavior, and flammability of these materials are compared. Both additives show submicron dimensions but differ in terms of particle and agglomerate sizes und shapes. The overall mechanical performance of the PBT flame-retarded with AlPi-Et is lower than that with AlPi-H-RXP, due to the presence of larger agglomerates. Moreover,

the flow behavior of the AlPi-Et/PBT materials is dramatically changed as the larger rod-like primary particles build a percolation threshold. In terms of flammability, both additives perform similar in the UL 94 test and under forced-flaming combustion. Nevertheless, AlPi-Et performs better than AlPi-H + RXP phosphatase inhibitor in the LOI test. The concentration required to achieve acceptable flame retardancy ranges above 15 wt %. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012″
“To correlate lower uterine segment (LUS) thickness measured by abdominal sonography at term pregnancy with that measured manually using caliper at cesarean delivery and to find out minimum LUS thickness indicative of its integrity in women with previous cesarean.

In 106 women with previous cesarean delivery and 68 with unscarred uterus, abdominal sonographic assessment of LUS was carried out within a week of delivery. Sonographic measurements were correlated with manual measurement of lower flap of LUS using Vernier calipers in 96 of these women (64 with previous

cesarean and 32 of unscarred uterus) who had elective cesarean delivery.

Sonographically Tideglusib determined LUS was thinner among women with previous cesarean delivery than in those without (4.58 SD 1.05 vs. 4.8 SD 0.8; t = 1.986; p = 0.04). Women with vaginal birth after cesarean had thicker LUS than women with repeat cesarean delivery (4.4 SD 0.97 vs. 4.48 SD 1.0). The findings were not influenced by engaged fetal head status or amount of bladder fullness. Directly measured LUS thickness using Vernier calipers before delivery of the baby confirmed ultrasound measurements, but showed smaller differences between them. There were eight cases with defective uterine scar at cesarean. LUS thickness at term of 3 mm provided 87.5% sensitivity and specificity, and was found to have negative predictive value of 98%.

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