Scientists from India performed an experiment where asphalt which is commonly used for road pavement was modified using castor oil based polyurethane to improve the properties of asphalt such as resistance to permanent deformation and to reduce the fatigue.
Polyurethane pre-polymer (PUP) was prepared by using castor oil and toluene diisocyanate (TDI). Asphalt modification was done using castor oil (C.O.) and PUP. Results showed that polymer modified asphalt showed improvement in properties such as hardness and softening point thereby making the pavement application smooth.
Scientists from Korea performed an experiment to fabricate castor oil/PCL based bio-polyurethane foam reinforced with nano cellulose. PU foam based on biomaterials was investigated to replace traditional petroleum-based polyol. Polyols were synthesized from castor oil (CO) and polycaprolactone (PCL). In addition, the effects of the nanocellulose on the thermal and mechanical properties of CO-based PU foam were investigated.
Results showed that addition of the nanocellulose could be an effective way to improve the mechanical and thermal properties of PU foams.
Researchers from Finland have found a method to produce novel castor oil segmented thermoplastic polyurethanes which have controlled mechanical properties.
Thermoplastic polyurethane (TPU) is an elastomer that is fully thermoplastic. Like all thermoplastic elastomers, TPU is elastic and melt-processable. TPU is a linear segmented block copolymer composed of hard and soft segments. The hard segment can be either aromatic or aliphatic. The soft segment can either be a polyether or polyester type, depending on the application.
The new study shows that it is possible to produce thermoplastic polyurethanes using castor oil via polyaddition approach where the formation of prepolymers needs to be carried out with the addition of small amount of castor oil and excess of diisocyanate in the very first step. This is followed by the addition of the other polyols and finally a low molecular weight chain extender.
Results showed that the synthesized polyurethanes exhibited good biocompatibility and high transparency.
Recent study shows that a two-step mediation of castor oil could overcome the problem of polyaddition threshold of castor oil during polyurethane formation.
The study has been conducted by scientists from India who have found that the mediation facilitates formation of polyurethane systems directly from castor oil without the need for triricinolein chain extension or the use of supplementary hydroxyl compounds.
The process involves refluxing castor oil with n-butyl lithium in the presence of a solvent followed by water addition.
Results showed that the mediation introduces two new compounds in castor oil namely, a lithiated diglyceride and a lithium salt of fatty acid. Characterization studies of the newly synthesized polyurethane were also carried out.
Recent study shows production of wood adhesives from castor oil.
Commonly used wood adhesives were anima (hide) glue, urea-formaldehyde resin adhesives, resorcinol-formaldehyde, phenol-formaldehyde, polyurethane, etc.
Now scientists from Iran have conducted an experiment to produce polyester polyols, which is an important compound in polymeric polyurethane adhesives, from castor oil. The polyester polyols were synthesized condensation polymerization of different dicarboxylic acids with castor oil.
Characterization studies were also carried out to determine the shear strength value in various conditions such as cold water, hot water, acid and alkali solutions.
Harvest of castor beans is being carried out in almost all the hamlets in Pachaimalai. The harvest process is being carried out only during late afternoon after allowing the seeds to dry. The oilseed is grown as an intercrop on the boundaries of tapioca farms along with local seeds.
Lack of attractive price for castor had forced the farmers to reduce the area under cultivation. An estimated 40 hectares has been brought under castor cultivation as against 200 hectares till a decade ago.
Recent study has found the use of castor oil as antistatic and anticorrosive materials.
Antistatic property is defined as the fast dissipation of static electricity (static charge). It is evaluated using two measures – surface resistance and half-life. The lower the surface resistance (Ω), the higher the antistatic property; and the shorter the half-life (s), the higher the antistatic property.
A previous study conducted by scientists from Korea in 2004, has found that waterborne -polyurethane coating materials containing conductive polyaniline blend films showed reduced antistatic half-life.
Now, scientists from Korea and India have prepared castor oil-based waterborne polyurethane/polyaniline (COWPU/PAni) conducting polymer blend films. The waterborne polyurethane synthesized from isophorone diisocyanate was reacted with castor oil to form prepolymers. Also, COWPU/PAni hybrid dispersions were synthesized to make different conductive composites.
Characteristic studies showed that COWPU/PAni conducting blend films could be used as antistatic and anticorrosive coating materials.
Scientists from Malaysia performed an experiment to compare the physico-chemical properties of high performance polyurethane prepared using pure poly propylene glycol (PPG) and that prepared from PPG and castor oil.
Characterization studies indicated the presence of large -CH stretching in castor oil mixed polyurethane with larger oxidative thermal stability over pure PPG polyurethane. The tensile properties were found to be almost comparable showing that mixed polymers can be used in future to overcome environmental and economic crisis.
Scientists performed an experiment to synthesize castor oil based hybrid polymers and their polyurethane urea-silica coatings. New acrylated alkoxysilane castor oil (AASCO) with hydrolysable –Si–OCH3 was synthesized from CO, maleic anhydride and 3-(Trimethoxysilyl) propyl methacrylate via free radical copolymerization method.
Characterization studies showed that castor oil modified silane based hybrid coatings had better mechanical, viscoelastic properties.
Researchers from Brazil performed an experiment to evaluate the feasibility of OSB panel production Parica (Schizolobium amazonicum) wood particles bonded by castor oil based polyurethane resin. Three different resin contents (8%, 10% and 12%) were evaluated.
Results showed that panels produced with 8% of resin content were best as they were compatible with norm requirements and used less resin in the manufacturing process. Thus Parica wood and castor oil based polyurethane resin in the OSB panels production is feasible.