Imperial Chemical Industries

About: Imperial Chemical Industries is a based out in . It is known for research contribution in the topics: Alkyl & Catalysis. The organization has 8189 authors who have published 7809 publications receiving 190252 citations. The organization is also known as: Imperial Chemical Industries Ltd.

Application of the "strathclyde route" to branched vinyl polymers in suspension polymerization: architectural, thermal, and rheological characterization of the derived branched products

Abstract: Copolymerizations of methyl methacrylate (MMA) and ethyl acrylate (EA), both monofunctional monomers, with ethylene glycol diacrylate (EGDA) as the brancher (a difunctional monomer) have been carried out via free-radical solvent-free suspension polymerization using 2,2′-azobis(isobutyronitrile) (AIBN) as the source of radicals, in the presence of a chain transfer agent (CTA) to avoid cross-linking and produce only branched polymers. Investigation of various CTAs led to the choice of 1-dodecanethiol (DDT) mainly due to its low volatility and hydrophobicity. Typically, EGDA/DDT mole ratios of ≤0.7 ensure that cross-linking is avoided. The molar mass and the branching architecture of the polymers have been characterized by MALS/SEC and the thermal and rheological behavior by DSC and melt rheology, respectively. The results confirm earlier indications from solution and emulsion polymerizations of the versatility of the “Strathclyde methodology” in producing branched polymers, in this instance in the form of f...

Observations on the uptake and translocation of five actinomycete antibiotics by cucumber seedlings

Abstract: The uptake and translocation of five actinomycete antibiotics by cucumber seedlings has been investigated by qualitative and quantitative techniques. Chloromycetin and streptomycin were absorbed from nutrient solution by the root system of cucumber seedlings and translocated to the leaves. The streptomycin concentration of leaf tissue increased with time to a level above that in the nutrient solution, whereas the chloromycetin concentration tended to remain constant at a level below that in the nutrient environment. Chloromycetin and streptomycin were identified in the leaf tissue of treated seedlings by paper chromatography. No convincing evidence of uptake and translocation of aureomycin, neomycin or terramycin was obtained.

Correlation of the cardiac sensitizing potential of halogenated hydrocarbons with their physicochemical properties

Abstract: The cardiac sensitizing potencies of a range of 14 halogenated hydrocarbons were assessed in conscious dogs by comparing the partial pressures (Pcs) needed to sensitize the heart to adrenaline. These were found to be directly related to their saturated vapour pressures (Ps) and the ratio Pcs/Ps was approximately constant although the values of partial pressures differed nearly 700-fold. It is suggested that cardiac sensitization is probably a structurally non-specific action and may be regarded as another example of physical toxicity.

Measurement of the strength of steric barriers in non-aqueous polymer dispersions

Abstract: The forces of repulsion generated in the steric barriers of a series of monodisperse spherical polymer particles, varying in diameter, have been measured using a surface balance. The particles were stabilized using a graft copolymer with a poly(methyl methacrylate) backbone and heptane soluble poly(12 hydroxy stearic acid) side chains. It was established that the particles were supported on a water surface and that the stabilizing polymer was in a heptane phase in the plane of compression. From pressure-area measurements, a stabilizing barrier thickness of 130 A (independent of particle size) was found which was in good agreement with the value from viscometry. Compression of the particles at the interface permitted the measurement of the collapse pressure of the steric barrier from which the work done in compressing the barrier was computed. Two theoretical models for the system, one similar to Fischer's treatment of osmotic pressure changes associated with the overlap, or inter-penetration, of the steric barrier and another based upon Ottewill and Walker's treatment of the free energy of dilution of the steric barrier have been evaluated. Both models are in good agreement with the experimental data.

The distribution in the body and metabolic fate of barbiturates

Abstract: THE metabolic fate and distribution of barbituric acid derivatives in the body has been the subject of a vast number of studies since they first began to be used in therapeutics in the early years of this century. The reviews of Lundy and Osterbergl, Tatum2y3 and Maynert and van Dyke4 are useful sources of information on articles on this subject printed before 1949. The aim of the present review is to describe recent advances in this field, together with the methods used. In it the author has tried to report, if not all, at any rate the most important contributions on this subject that have been published since that date. It should be mentioned that the expression barbiturate has been used for both barbituric and thiobarbituric acid derivatives used clinically.