Articolele autorului Alex Dragomirescu
Link la profilul stiintific al lui Alex Dragomirescu

The Hell Might Be Green
Water Absorption Performances in WPC Materials

The tendency of wood-plastic composites (WPC) to absorb moisture is very important in the processing and also in mechanical properties, appearance, dimensions. Swelling of natural fibres can lead to cracking of the material, degradation and poor mechanical properties. The potential effect of water absorption on WPC composites is discussed based on known results from a long experience in testing Enviroshake® engineered roofing material. This presentation

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Synthesis and Characterization of Hyperbranched Polyisobutylene

The 4-(1-methoxy-1-methyl-ethyl)-styrene inimer was successfully synthesized and characterized. Gel-free high molecular weight hyperbranched PIBs(3< BR < 60) were prepared (1 pound per batch). Molecular weigths up to 1.04x106 g.mol-1 and MWD as low as 1.2 in only 15-60 minutes reaction time were achieved. Preliminary viscoelastic and technical characterization revealed very interesting properties.

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Modeling of Industrial Polymerization Reactor for Low Density Polyethylene

Developed a reliable model based on long-term operation data for optimization of high-pressure polyethylene reaction section. Conceptualized a software package written in FORTRAN for on-line operation of this specific polymerization reactor.

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Highlights of Research and Development – Success Stories
Pour Point Depressants for Improving The Filtration Capacity and The Limit Temperature of Diesel Fuels

The additives are based on copolymers of vinyl acetate and mixed maleic acid or fumaric acid esters, comprising 64-66 wt.% copolymer, contg. 70 mol% vinyl acetate and 30 mol% C8, C16-18 alkyl diesters of maleic acid or fumaric acid, in 33-36 wt% toluene. The copolymer is prepd. by polym. of vinyl acetate with a diester of maleic acid contg. 65-70 mol% C16-18 ester and 30-35 mol% C8 ester or a diester of fumaric acid contg. 55 mol% C8 ester and 45

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Lubricating Oils Additives Based on Diene-Styrene Copolymers
The Hydrogenation of Diene-Styrene Copolymers
Contributions to synthesis of additives designed to improve oil product flow

The doctoral thesis goal is to synthesize new additives to be used as superior flow improvers for the oil products. The selection of the research field has followed to a thorough study of the scientific literature concerning flow improvers and their action on paraffin crystal growth at low temperatures. The chosen field is that of diene-styrene polymers based additives, which are currently less known and used. I have approached the additive preparation

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Practical Approach to Monitor Adsorption/Drying and Catalytic Activity On-line

This thesis discusses the practical application of a recently developed on-line monitoring technique based on localized DC resistance measurements in a packed bed column. Two examples will be presented: 1) Monitoring the movement of the adsorption front in an industrial drying column; 2) Monitoring the catalytic hydrolysis of methyl chloride in an alumina packed bed. The two examples are related since the products of the catalytic hydrolysis are

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