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Copolymers of different concentration of decyl acrylate and 1-decene with rice bran oil were prepared and their characterization was carried out by spectral (NMR, IR), thermogravimetric, and gel permeation chromatography analysis. Performance evaluation of them in lube oil indicates that the polymers effectively act as pour point depressant and viscosity modifier. The viscosity index and pour point values depend on the nature of mineral base oils, polymer type, and also on the concentration of the additives in solution. Biodegradability test was also carried out and as anticipated, the rice bran oil–copolymers showed excellent biodegradable nature among the additives. [ABSTRACT FROM AUTHOR]

Homopolymers of isodecyl acrylate and isooctyl acrylate and copolymers of each of them with β-pinene (BP) were synthesized and characterized by spectral, thermogravimetric, and gel permeation chromatographic analysis. Pour point depressant (PPD) and viscosity index improver (VII) properties were tested with additive-doped base oil in terms of pour point (PP) and viscosity index (VI), respectively. Although the isodecyl acrylate polymers were thermally more stable than the isooctyl acrylate polymers, the latter showed higher VI and PPD efficiency. VI and PP values of the additive-doped base oils depend on the nature of mineral base oils as well as on the type and concentration of VII. In addition, introduction of BP moiety in the acrylate backbone has induces excellent biodegradability in the above polymers. [ABSTRACT FROM AUTHOR]

Methacrylate based lube oil additive of three different kinds viz, one homopolymer (polyhexadecyl methacrylate [PHDMA]) and two of its copolymers (HDMA-1-decene and HDMA-styrene) have been synthesized, characterized and investigated for their viscosity modifier (VM), antiwear (AW), and thickening performance at different concentrations in two different base oils. The VM properties in terms of viscosity index (VI), the AW properties through determination of wear scar diameter (WSD) using a four ball wear tester and thickening (i.e., rise in oil viscosity due to added polymer at a given polymer concentration was studied). The polymers studied have been found to show VM and AW properties under the experimental conditions. At a given polymer concentration thickening was found to increase in the order PHDMA-styrene > PHDMA-1-decene > PHDMA. The intrinsic viscosity, a measure of polymers hydrodynamic volume, showed a higher value in lower viscosity base stock, as compared to the higher viscosity oil in the case of homopolymer and PHDMA-1-decene copolymers. The decrease in viscosity with temperature followed the order PHDMA > PHDMA-1-decene > PHDMA-styrene; indicating a better viscosity index for the styrene copolymer (PHDMA-styrene). [ABSTRACT FROM AUTHOR]

A comparative study of additive performance (viscosity modifier [VM], pour point depressant [PPD], and anti wear [AW]) of homo polydecylacrylate (D) and its blend with three different types of liquid crystals (each containing three samples) has been performed. Very low concentrations (100 ppm) of liquid crystals are used in this study and processes include synthesis of D, characterization (FT-IR, NMR) and evaluation. A comparison based on performances has been made among the three different series of liquid crystals (LC) blended homo polydecylacrylate (D). The study indicates the LC blended additives are far better in AW performance compare to only D and their VM and PPD properties are comparable with D and amongst all the three series of liquid crystals, AW performance is better for long alkyl chain length sample. Multifunctional additive performance of this kind of LC blended polyacrylate is reporting for the first time. [ABSTRACT FROM AUTHOR]

Polydecylacrylate (PDA) is synthesized, characterized (FT-IR and NMR), and evaluated for its performance as anti wear (AW), pour point depressant (PPD), viscosity modifier (VM), and thickening agent in lube oil of different compositions. In addition physical blend of it with liquid crystal (LC) of cholesteryl benzoate (CB) is also made and evaluated, and the data is compared. Molecular weight of the prepared polymer and that of it blends was determined by viscometric analysis. The blends showed better efficiency to act as multifunctional (AW, PPD, VM) additives compare to the pure homopolymer in lubricating oil. [ABSTRACT FROM AUTHOR]

Aim: The value of polythene film ('cling wrap') to improve thermal control and reduce postnatal weight loss in preterm, very low-birthweight babies was investigated. Methods: Consecutively born babies with birthweights between 750 and 1500 g were stratified by birthweight (<1250 g, 1251–1500 g) and randomised either to the cling wrap (CW) or no cling wrap (NCW) group. The baby bassinette of the RW was covered with cling wrap up to the level of the neck in the CW group for the 1st 7 days. The primary outcome variables were the incidence of hypothermia (axillary temperature ≤36°C) after initial stabilisation during the first 7 days and cumulative weight loss (percentage of birthweight) at 48 hours of age. Results: Of 51 babies, 26 were randomised to the CW and 25 to the NCW group. None of the babies in the CW group developed hypothermia in the 1st 7 days but 36% in the NCW group (p = 0.001) did. Babies who were hypothermic on admission took less time to reach normal temperature in the CW group. Cumulative weight loss in the 1st 48 hours was 5.0 + 5.6% in the CW group and 8.6 + 7.0% in the NCW group (p = 0.06). Conclusion: Use of CW might be a simple method of maintaining temperature in very low-birthweight babies in developing countries. [ABSTRACT FROM AUTHOR]