a very efficient one-pot three-component synthesis of pyran derivatives has been improved by condensation of aldehydes and malononitrile with dimedone under 80 °c using sucrose as natural and biodegradable catalyst in water. this method offers some advantages including inexpensive, high to quantitative yields, short reaction time, and easy work-up. therefore, this methodology is entirely green ...

New biodegradable surface active agents were prepared by glycosidation of prehydrolysis lignin with the D-glucose using anhydrous ferric chloride as the catalyst which afforded polymeric alkyl, benzyl and aryl glucofuranoside derivatives of lignin. Moreover, a series of novel lignin-based surface active agents was obtained by subsequent Oxidation of the primary alcohol groups of u-glucose into ...

Biodegradable aliphatic random copolyesters poly(butylene succinate-co-butylene adipate), PBSA and poly(butylene succinate-co-butylene azelate), PBSAz were synthesized from 1,4 butane diol, succinic acid and adipic acid/azelaic acid through direct melt polycondensation with Titanium Tetra isopropoxide (TTiPO) as a catalyst. These polyesters were characterized by Viscosity measurements, 1H NMR s...

A novel and cost-effective catalyst for synthesis of 2,3'-dihydroquinazolin-4-(1H)-ones was developed utilizing a combined nanocomposite obtained from bonding TiCl3 to hydroxyl groups of nanofibrillated cellulose as a green and inexpensive support.The structure of the catalyst was investigated using the Fourier transform infrared spectroscopy (FT-IR), field emission scanning...

Polycondensation and ring-opening polymerization are two important polymer synthesis methods. Poly(lactic acid), the most typical biodegradable polymer, has been researched extensively from 1900s. It is of significant importance to have an up-to-date review on the recent improvement in techniques for biodegradable polymers. This review takes poly(lactic acid) as the example to present newly dev...

As a result of declining oil reserves in the world, the rise in fossil fuel prices and growing interest in the environment, there is considerable demand for alternative fuels. Biodiesel is recognized like the "green fuel" and has several advantages compared to diesel. It is safe, renewable, nontoxic, and biodegradable (98% biodegradable in a few weeks). Contains less sulfur compounds, and has a...

In recent year, biocompatible, biodegradable materials (linear polylactic acid-based urethanes) in the solid and/or liquid form have attracted tremendous attention in biomedical application particularly in stent coating. Low molecular weight poly (lactic acid) s (PLA), having narrow molecular weight distribution was by dehydropolycondensation method using tetraphenyltin as a catalyst. Hydroxyl ...

     A very efficient one-pot three-component synthesis of pyran derivatives has been improved by condensation of aldehydes and malononitrile with dimedone under 80 °C using sucrose as natural and biodegradable catalyst in water. This method offers some advantages including inexpensive, high to quantitative yields, short reaction time, and easy work-up. Therefore, this methodology is entirely g...

Nano-cellulose with high amount of free OH groups could be used as supporting agents for boron trifluoride (BF3). Nano-BF3/cellulose is a solid acid and a biodegradable catalyst which was prepared via reaction of nano-cellulose and BF3. The structure of this catalyst was studied by FT-IR, FESEM, TEM, XRD, EDS, TGA, XRF and BET. In this research, the synthesis of...