International Conference and Exhibition on Polymer Chemistry November 14-16, 2016 Atlanta, Georgia, USA

Diptesh G Naik is pursuing his Doctoral degree under the guidance of Prof. Vishnu S Nadkarni at Goa University since 2012. He has completed his Master’s degree from Goa University, Goa in the year 2009 securing 3rd rank in Physical Chemistry. He has 2 publications in international journals and 1 Indian patent.

In 1958, D A Young detected latent tracks in LiF crystal which lead to development of a new field solid state nuclear track detection (SSNTD) technique. After the invention, many materials like minerals, glasses, plastics, etc. were used as detectors in SSNTD application. For the first time, in 1966, K. Becker used phosphate glass as nuclear track detector. Barium phosphate BP-1 glass, LG-750 phosphate glass and various other sensitive phosphate glasses have been utilized as track detectors. Eventually, it was found that glass detectors showed poor radiation sensitivity as compared to many plastic detectors. Plastic materials like cellulose nitrate, bisphenol-A polycarbonate (lexan), poly (allyl diglycol carbonate) (CR-39), etc. were then used as track detectors. Out of which CR-39 was found out to be the best detector with high radiation sensitivity compared to all other detectors. Most of the reported polymeric track detectors have either -SO2-, -SO3-, -CO3- or - ONO2 linkage; there are no reports about the use of phosphate-carbamate containing polymers in track detection. Already, we have reported the application of poly triallyl phosphate PTAP and their copolymers with allyl diglycol carbonate (ADC) in international journal. At Goa University, we are involved in developing polymeric track detectors containing different radiation sensitive functionalities. Here, we report preparation of some novel polymeric track detectors having carbonate-phosphate; carbamate-phosphate linkages for their use in SSNTD. Poly (triallyl phosphate-co-pentaerythritol tetrakis allyl carbonate) i.e. poly (TAP-co-PETAC) and poly (triallyl phosphate-co-N-allyloxy diallyl carbamate) i.e. poly (TAP-co-NADAC) were prepared and successfully tested for SSNTD application. The alpha sensitivity as well as alpha track detection efficiency of the copolymers was compared with that of imported CR-39. It is observed that the alpha sensitivity of the copolymers was much better than that of CR-39.

Maria de los Angeles Vargas has completed her PhD from Mexico University and Post-doctoral studies from Institute of Technology Karlsruhe in Germany. She has a Lecturer position at the Higher Education Technology in Chemical Engineering Department, Mexico. She has published more than 16 papers in reputed journals and book chapters in NMR at 20 MHz: Possibilities and Challenges.

The curing kinetics of UP nanocomposites prepared by incorporating different amounts of two kinds of organo-montmorillonite (organo-MMT): trimethyloctadecacylammonium chloride (TMOA) and aminopropyl-triethoxysilane (APTES) were studied by non-isothermal differential scanning calorimetry (DSC) experiments. Small angle X-ray scattering (SAXS) was used for measuring the d-spacings in the modified organo-clays, and no intercalation UP into these clays was observed for the nanocomposites. HRTEM images showed dispersed and agglomerated platelets in UP/APTES 2 and 10 wt.%. DSC analysis showed two peaks in UP resins and UP/organo-MMT, and a decrease in the exothermal peaks temperature (Tp1 and Tp2) for nanocomposites with the heating rate as compared with those of neat UP system; thus, the higher the heating rate, the higher the curing reaction rate. This effect was more clearly on the UP/MMT-APTES nanocomposites. The effective activation energies (Ea) were determined with the mode-free isoconversional Starik’s method. Sesták–Berggren model was chosen to simulate the reaction rate with a good match achieved. Thermal gravimetric analysis showed that the cured UP/APTES at high concentration were slightly more stable than UP and TMOA.

Dr. Lakshmi C. Kasi Viswanath is currently working as an assistant professor at Oklahoma Baptist University.\r\nHer research focus lies on supramolecules,development of donor acceptor conjugates for organic solar cells\r\nand light harvesting systems. She has published many articles in international journals including a book\r\nchapter. She also serves as a reviewer for reputed journals and also a member of editorial board. She\r\nactively participates in ACS conferences.

A series of symmetrical chiral, liquid crystal dimeric molecules possessing ester-linked, biphenyl-naphthyl cores with varied spacer\r\nlengths and terminal vinyl groups have been synthesized. (S)-(+)-2-(6-Methoxy-2-naphthyl)propionic acid was used as the synthetic\r\nprecursor to achieve the target dimers. The synthesized symmetrical chiral dimers were characterized by 1H NMR spectroscopy, and\r\ntheir liquid crystalline behavior was confirmed by DSC and HOPM studies. Structural effects on the mesomorphic and\r\nphysicochemical properties were investigated in terms of variation of chiral chain length. The synthesized dimeric compounds\r\nexhibited SmX*, SmC*, SmA*, N*, BPI*, and BPII* mesophase sequences. An odd-even effect was observed in which the dimers\r\nwith an even number of spacers generated SmX*, SmC*, SmA*, N*, BPI*, and BPII* phases whereas dimers with an odd spacers\r\nexhibited SmX*, SmA*, N*, BPI*, and BPII* phases, and the duration of the mesophase decreased with increasing spacer length.\r\nThe differences in transitional properties for odd- and even-numbered dimers could be attributed to the difference in conformation of\r\nthe molecules of the liquid crystalline dimers. When the number of methylene units in the bridging chain (spacer) is odd, then the\r\nspacer will be in its cis conformation, which causes the two aromatic units to be tilted in the same direction with respect to eachother\r\n(Fig. 1A). In the even membered dimers since the aromatic units are tilted in the opposite directions, a bent structure is produced\r\nwhich when packed with other dimers together will lead to a zig-zag layer-like structure. In general, the trans conformation (Fig.\r\n1B) always leads to layer regularity and promotes the crystal-crystal polymorphism. This kind of layer formation may assist the\r\nformation of SmC* phase. However, the cis conformation destroys the regularity and as well as the polymorphism in the liquid\r\ncrystal melt. The synthesized vinyl substituted liquid crystalline dimers are particularly useful in understanding liquid crystal\r\npolymorphism and act as model compounds for liquid crystal polymers.