Castor oil/polystyrene

Figure 2. Reaction scheme for castor oil/polystyrene SIN s. Samples were removed for optical microscopy, followed by centrifugation. The volume fraction and viscosity of each phase fraction was determined for values used in equation (2).

Both the elastomeric and the plastic castor oil/polystyrene SINs exhibit significant toughening/ " " The synthesis of these materials is discussed in Sect on 5.5.2. Figure shows the stress-strain behavior of COPEN,... 

Table 7.4. Tensile Properties of Castor Oil/Polystyrene SINs at Ambient Conditions Elastomeric Compositions ...

Simultaneous Interpenetrating Networks Based on Castor Oil Elastomers and Polystyrene A Review of an International Program... 

The main path of the research employed both methods of synthesis in turn. At first, the graduate students Yenwo and Pulido explored the use of sequential IPN s based on castor oil urethanes and polystyrene (12-16). At the same time, the graduate student Devia, working in Colombia, explored an alternate synthetic route using latex technology (17). Since nothing was known about the behavior of such materials, their collective objective was to provide a map upon which further efforts could be intelligently based. This effort has now been reviewed (18). 

By comparison, the synthesis of SIN s involved a castor oil derived crosslinked elastomer and crosslinked polystyrene as... 

Table 1. Glass Transition Temperature of SIN s Based in Castor Oil Elastomers and Crosslinked Polystyrene (%V...

Since the purpose of this paper is to review the synthesis and behavior of SIN s based on castor oil elastomers and cross-linked polystyrene, a summary of the main results and conclusions of this study is given below (Refer to Ref. 22.)... 

Based on castor oil derived elastomers and crosslinked polystyrene, a simultaneous mode of polymerization can be successfully employed to synthesize prototype engineering materials such as tough, impact resistant plastics and reinforced elastomers. 

The SIN s from castor oil and the other oils were tough materials, either reinforced elastomers or impact resistant plastics depending on their composition and whether phase inversion had occurred. Impact strengths in the range of 40-60 J/m were obtained. The glass transitions of the rubber phase of the SIN s tended to be a little higher than those shown in Table IV. The polystyrene phase... 

Castor oil and other special function group triglyceride oils can be made into low T elastomers. In SIN form with polystyrene, a... 

Siddaramaiah et al. (86) employed an X-ray diffraction method to determine the microstructural parameters of IPNs of castor oil-based polyurethanes and polystyrene and correlated the changes of microstrucmral parameters to the physical macro changes, such as hardness. They found that the addition of polystyrene (PS) resulted in an increase in hardness that was due to an increase in crystal size. 

Zinc and castor oil cream was tested in a polystyrene jar using a four start lug finish to simplify removal of the closure (mother holding baby). Samples were stored at 4°C, 20°C, 30°C and 37°C. Jars cracked at the four stress points created by the four lug closure, first at 4°C then at the higher temperatures in ascending order of temperature (i.e. 6 weeks, 3 months, 7 months, 10 months). The subsequent use of an impact modified polystyrene with the return to a conventional continuous screw thread and screw cap ultimately provided a satisfactory pack. 

Simultaneous IPNs are formed by homogeneously mixing together monomers, prepolymers, linear polymers, initiators, and crosslinkers, The monomers and prepolymers are simultaneously polymerized by independent reactions that differ enough to avoid interfering with each other. For example, a polyure-thane/polymethacrylate and a polyurethane/polystyrene were made in a process in which both monomers were prepolymerized, dissolved together, and reacted to form an IPN. Another urethane system was made from castor oil reacted with toluene diisocyanate and sebacic acid polyesters. The resultant urethane prepolymer was then mixed with polystyrene to form an IPN. 

Compared to aliphatic hydrocarbons, aromatic hydrocarbons (DIN 51633) have a higher solvency for oils, castor oil, oil-modified alkyd resins, styrene-modfied oils and alkyd resins, saturated polyester resins, polystyrene, poly(vinyl ethers), polyacrylate and polymethacrylate esters. poly(vinyl acetate), vinyl chloride and vinyl acetate copolymers, and many low-polarity resins. 

Diacetone alcohol [123-42-2] (4-hydroxy-4-methyl-2-pentanone) is an almost odorless ketone alcohol that is weakly acidic as a result of rearrangement to the enol form. It is miscible with water and organic solvents except aliphatic hydrocarbons. It acts as a good solvent for cellulose esters and ethers, alcohol-soluble resins, castor oil, and plasticizers. Poly(vinyl acetate) and chlorinated rubber are partially dissolved or swollen. Polystyrene, poly(vinyl chloride), vinyl chloride copolymers, dam-ar resins, resin esters, rubber, bitumen, mineral oils, ketone resins, and maleate resins are insoluble. Diacetone alcohol is used as a high boiler in stoving enamels to improve flow and gloss. 

Methyl glycol [109-86-4] (2-methoxyethanol, ethylene glycol monomethyl ether) has a slight odor, and is miscible with water and organic solvents except aliphatic hydrocarbons. It is a very good solvent for many natural and synthetic resins. It does not dissolve fats, oils (except castor oil), damar resin, rubber, bitumen, hydrocarbon resins, polystyrene, poly(vinyl chloride), and vinyl chloride copolymers. On account of its teratogenic properties it is replaced as a solvent in the paint and colorants sector by other solvents or solvent mixtures. 

Experimental studies by Fiiredi and Valentine at various frequencies involved the bunching and orientation of microscopic particles made of polystyrene spheres, aluminum or carbon particles, ion exchange resin beads, ferric oxide or potato starch particles in water, saline solutions, or in castor oils. Orientation effects appeared to be absent in the salt solutions, but to be accentuated in castor oil, relative to that in water especially at high frequencies. GrifBn and Stowell confirmed and extended the studies of Teixera-Pinta et on the bunching and orientational effects of... 

Opacarb PCC. See Calcium monocarbonate Opacifier 614 Latex. See Polystyrene Opacimite . See Calcium carbonate Opacitex . See Kaolin, calcined Opalwax. See Hydrogenated castor oil Opaseal . See Polyvinyl acetate phthalate Opazil . See Bentonite OPD. See o-Phenylenediamine Opex 80. See Dinitrosopentamethylene tetramine... 

In order to synthesize the IPN, the urethane elastomer was swelled with styrene containing 0.4% benzoin as initiator and 1% divinylbenzene (DVB) as crosslinker. Polymerization of the styrene was carried out by ultraviolet radiation at room temperature for 24 hr. The corresponding castor oil-poly ester/polystyrene SINs are discussed in Section 5.5. 

Castor oil-sebacic acid polyesters and polyurethanes were prepared in SIN form with polystyrene by Devia et Since sebacic acid is... 

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