Effect of Processing Parameters on Polymerization of P3HT in Presence of CdS

Negatively Charged Poly(acrylic acid) Side Chains Grafted onto Poly(3-hexylthiophene): Impact on the Structural Order and Molecular Dynamics

“…The integration of the peaks originating from αmethylene protons (next to the thiophene ring) of the 3substituents can also be used as a probe for studying the regiochemistry of the P3HT-g-PAA graft copolymer as it gives insight into the head-to-tail (HT) and head-to-head (HH) couplings (Figure S4). 75,77,79 The α-methylene proton peak at 2.57 ppm with a fraction of 0.3 is assigned to the HH configuration, while the one detected at 2.81 ppm with a fraction of 0.7 is attributed to the HT regioisomer. 82,83 These findings confirm the presence of domains with different order in the P3HT-g-pAA which is in line with XRD and spectroscopic data.…”

“…Hence, it can provide information on the structure and regiochemistry of P3ATs. The pairwise coupling of 3-substituted thiophene monomers via the 2- and 5-positions yields head-to-head (H–H), tail-to-tail (T–T), and head-to-tail (H–T) regiochemical isomers (dyads) with different degrees of regioregularity. − P3AT polymers that include a mixture of these couplings in the form of four triad regioisomers (Scheme ) are called regiorandom. ,, On the other hand, polymers that encompass only HT–HT coupling are called regioregular. ,, The spectral features of the β-protons in the 6.90–7.20 ppm region reveal configurational and regiochemical characteristics in the polymer. , The β-proton can have four different chemical environments in the combination of four possible triad regioisomers. Representative 1 H NMR and HSQC spectra of the P3HT- g -PAA graft copolymer in the thiophene region of chemical shifts are shown in Figures and S2.…”