Question

Problems 101 2 CH-CH-CH-S-CH-CH-CH, A CH, CH3)4CH, SH B CH, -CH-CH:-0-CH-CH2-CH, CH-CH-CHU-0 H с D HUMBERS 6. The infrared spectra of some polymeric materials follow. Assign a structure to each of them, selected from the following choices: polyamide (nylon), poly(methyl methacrylate), polyethylene, polystyrene, and poly(acrylonitrile-styrene). You may need to look up the structures of these materials. MORO 14 200 2000 9900 1400 1200 WAVENUVIDERSION) 1000 MICRONS 1 12 13 14 15 TRANSMITTANCE man 1730 cm 1600 1200 1000 600 WAVENUMBERS

Answer 1

absorption frequency intensity group broad (Strong) -OH Strech 3300 - 3900 cm medium -SH Group 2400 cm strong C-o-c strech 1150-1010 cm Cether) c-s-c (strech) Strong 1500-1400 cm Strong oly -C-NH2 1690 cm strong - E of ester 1730(m Ester c-o strech 1300-1100 cm Two bands Strong =C-H Strech Caromatics niedium 3100-3000 cm weak Overtones of aromatic bencene. 2000-1500 cm 1500 em C-C Sheching in Shong aromatic ring

1. we obser strong peak around 1500-1400 can indicates c-s-c strech. strong peak at 3000- 2800 crni indicates C-H Strech For -Oh broad signat at 3300-3500 cm abscence of OH group For SH , medium peak at 2400 cm, not observede abscence of SH group. For ether, c-o-c Strech at 1170 - 1150 stong not observed absence of ether. So, the compound it this ether ie CH3-CH2=CH2-S-CH2-CH2-CH3 A 2. > peak at 3100 - 3000 (m' indicates aromatic =ct Group Strong indicates със Peak between 1450-1500 (m' Strech in aromatic ymg peak between 1800-2000 cmai indicates aromatic ring overtonef

So, the structure it polystyrene FGH CH₂ In 3 Speak at 1730 cm strong indicater ester Carbonyl ELO Lo Group 1300-1100 cm indicates ester Two peaks at Skech. C-o The compound polyester ie poh imethyl methyl acrylate) CH3 [Chord In -OCH3 ester GYOUP