Semi-interpenetrating polymer networks prepared from in situ cationic polymerization of bio-based tung oil with biodegradable polycaprolactone

Abstract

In situ cationic polymerization of bio-based tung oil in the presence of poly(ε-caprolactone), a crystallizable, biodegradable, and biocompatible polymer, was performed to produce novel semiinterpenetrating polymer networks (IPNs). The macromolecular structure and properties of these IPNs were investigated as a function of composition using small amplitude oscillatory shear flow rheology, FT-IR spectroscopy, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). This versatile and low-cost strategy successfully produced bio-polymer blends with various degrees of miscibility, morphology, and crystallization behavior. The carbon-carbon double bonds in tung oil were consumed quickly after adding the cationic initiator to form a three-dimensional (3D) crosslinked network in all measured samples as confirmed by FT-IR. A complete miscible structure with a single glass transition temperature and onephase morphology was observed for a tung oil/PCL 90/10 blend. On the other hand, a two-phase structure exhibiting a nanoscale morphology of the dispersed minor phase as small as 100 nm was observed for blends with 20 and 30 wt% PCL. For a 50 wt% PCL blend, an interconnected, co-continuous microstructure of the two phases was also detected. DMA and DSC measurements confirmed the miscibility (or partial miscibility) of the blends by following the changes in the glass transitions of phases as a function of the composition. The value of the elastic modulus (E′) in the glassy state as obtained from the DMA measurements was strongly dependent on the composition, reaching a maximum at 20 wt% PCL.

Novel bile acid sequestrant: A biodegradable hydrogel based on amphiphilic allylamine copolymer

“…At the crossover time (t gel ), the mixture exhibited dominant elastic property rather than the previous pure viscosity. 37 Afterwards, the values of G′ and G′′ reached a plateau at the end of the cross-linking reaction. The whole evolution followed a typical behavior of a gelation process.…”

Biorenewable thermosetting copolymer based on soybean oil and eugenol

“…The gelation time can be found at the intercept of storage modulus and loss modulus curves [54]. The value of the gelation time is found to be dependent on the chemical composition of the AESO/ME copolymer.…”

Preparation and properties of epoxy‐modified tung oil waterborne insulation varnish

“…As the above adduct was cooled down to 1158C, 10 g n-butanol, and 20 g PEG-1000 were added and the reaction was kept for 2 h. At the same time, required amount of epoxy resin (10,15,20,25, and 30%, based on the weight of tung oil) were dissolved in the equal amount of medium composed of ethylene glycol butyl ether and n-butanol with the volume ratio of 2 : 3 at 658C. The predissolved epoxy resin was added dropwise into the flask when the temperature was cooled to 908C, and then the calculated triethanolamine (1%, based on the weight of epoxy resin) was added into the system to catalyze the reaction for 2.5 h. When the system was cooled to room temperature, 10 g isopropanol, and 10 g propylene glycol monomethyl ether were added.…”

“…17,18 Much valuable work has been done on the investigation of waterborne epoxy resin 19,20 or waterborne polymer composites based on epoxy resin. 1,8,21,22 Seed oils have been traditionally used as resins or components in organic coatings, 23,24 due to their appealing advantages such as easy availability, environmental friendliness, inherent biodegradability, 25 low cost, and easy modification. [26][27][28] Tung oil, a kind of seed oils extracted from the seeds of tung tree, is a promising resultant material in China, 29 which shows the advantages of faster drying, better water resistance and higher hardness.…”