P toluenesulfonic acid ptsa

3-hexathiophene (3HT, 98.0% purity, TCI) was the starting monomer. Ferric chloride (FeCl₃; 97% purity, Sigma Aldrich, St. Louis, MO, USA) was the oxidant used. Chloroform (CHCl₃; AR grade, RCI Labscan, Bangkok, Thailand) was the solvent. Dodecylbenzenesulfonic acid (DBSA; 98% purity, Sigma Aldrich), p-toluenesulfonic acid (PTSA; 98.5% purity, Sigma Aldrich), sodium dioctyl sulfosuccinate (AOT; 96% purity, Sigma Aldrich), and sodium dodecyl sulfate (SDS; 98% purity, Sigma Aldrich) were the surfactants. Methanol (99.8%), toluene (99.5%), and hexane (99.8%) were obtained from RCI Labscan. For the de-doping and doping processes, ammonium hydroxide (NH₄OH; 30% v/v, Panreac, Barcelona, Spain) was used to de-dope the P3HT_DBSA powder, whereas perchloric acid (HClO₄; 70% v/v, Panreac) was the dopant. All reagents were of analytical reagent grades and were used without modification.

1,1,1-Tris(hydroxymethyl)propane
was purchased from Sigma-Aldrich. It was dissolved under reflux in
acetone, precipitated with ethyl ether, and then dried prior to use.
NaH (60 wt %) in mineral oil was purchased from Merck. The oil was
removed by washing with dry 1,4-dioxane and then drying under reduced
pressure. Glycidol (Sigma-Aldrich) was dried over CaH₂ and
distilled before use. Tetrahydrofuran (THF) was purchased from Sigma-Aldrich
and dried over Na/K alloy. 2,2-Dimethoxypropane (TCI), benzoyl chloride,
phenyl isocyanate (Alfa Aesar), and 4-biphenylyl isocyanate (Sigma-Aldrich)
were used as received. p-Toluenesulfonic acid (PTSA)
was purchased from Sigma-Aldrich and dried with benzene before use.
CLT (Sigma-Aldrich) was used as received. Clodital MAX 500 mg, USP
Health, a CLT-loaded commercially available tablet, was used as a
reference.

Several biomaterials were used as feedstock for the liquefaction process. Pinewood shavings (hereafter referred to as pinewood) were used as reference biomass. The Leiria National Park kindly supplied samples of slices of burned pinewood obtained from the fires of 2017. For liquefaction, five fractions were considered: bark, sapwood, heartwood, branches (Figure 1), and commercial pinewood shavings. The pine branches were collected from the forest ground.
Firstly, the biomass samples were cut into small cubes (Figure 1c) and dried in an oven at 110 ± 3 °C for 24 h. The drying process was conducted to facilitate the characterisation since it has no impact on the liquefaction process. Afterwards, the cubes were shredded in a Retsch© SM 2000 mill equipped with a 4 mm sieve to increase the contact surface area between the solvent and the feedstock. The reagents were: 2-ethylhexanol, purity ≥ 99%, p-toluenesulfonic acid (PTSA), purity ≥ 99%, from Sigma-Aldrich, and acetone, technical grade, acquired from a local gross supplier.