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The purpose of the present study was to investigate the effect of the electroless Ni–Cu–P-PTFE deposit surface on anti-fouling of heat exchangers, which was considered as a way to mitigate the accumulation of mineral fouling in the heat exchangers. Electroless Ni–Cu–P-PTFE deposits with various PTFE content were prepared on mild steel (1015) substrate surface by different process parameters. Surface morphology and microhardness were investigated by using SEM, MH-6 Vickers, respectively. The results showed that the addition of PTFE particles into the Ni–Cu–P matrix hardly affected the microstructure of the deposits. Microhardness was decreased with the addition of PTFE in the deposits. Moreover, the surface free energy of Ni–Cu–P-PTFE deposits was decreased with the increase of PTFE particles in the deposits. Further fouling experiments indicated that the surfaces of Ni–Cu–P-PTFE deposits with different PTFE content inhibited the adhesion of fouling compared with the mild steel surface of the heat exchangers. The adhesion weight of fouling was approximately in inverse proportion with the addition of PTFE particles in the deposits, but not the value of surface roughnesss. The anti-fouling property can not be improved ideally even considering the option of making Ni–Cu–P-PTFE coatings smooth.

A fast approach was described for the synthesis of water-dispersible monodisperse dopamine-coated Fe3O4 nanoparticles (DA-Fe3O4) with uniform size and shape via ligand-exchange of oleic acid on Fe3O4 using only 2 min. The prepared DA-Fe3O4 nanoparticles were characterized by transmission electron microscopy, Fourier transform infrared spectrometry, and vibrating sample magnetometer. The results indicated that the resulting DA-Fe3O4 nanoparticles had an average diameter of about 19.2 nm. The magnetic saturation value of the prepared DA-Fe3O4 nanoparticles was determined to be 72.87 emu/g, which indicating a well-established superparamagnetic property.

The polymerizations of 2-methyl-2-butene (2M2B) were carried out by various cationic initiators in different media at 30°C. All these polymerizations generate oily oligomers of rather low degrees of polymerization (3–5). Evidences from i.r. and 1H n.m.r. show that the oligomer chain contains structural units derived from both 2M2B and 2-methyl-1-butene (2M1B), which indicates that 2M2B isomerizes partially to 2M1B during the polymerization. The unsaturated endgroups also arise from chain transfers of both 2M2B and 2M1B growing carbocations by proton-elimination. The reaction carried out in toluene fails to produce any polymer or oligomer but generates an adduct of 2M2B and toluene by Friedel-Crafts alkylation.

A kind of surfactants with a polymerizable end-group were synthesized. A nanometer polymer latex dispersion has been prepared in the presence of one of the above polymerizable surfactants. The latex particle size is in the range of 20–40 nm. An environmentally friendly water-based coating based on the above nanometer polymer latex dispersion has been prepared and the preparation process has been optimized. This water-based coating has been characterized and the results have shown promising properties comparable to the conventional solvent-based coatings.

Resume Les polymerisations du 1,3-pentadiene amorcee par le triflate d'aluminium (trifluoromethanesulfonate d'aluminium) ont ete etudiees en fonction de differents parametres (temperature, polarite, concentration en amorceur et concentration en monomere). Il a ete montre que la polymerisation etait possible a temperature ambiante (20°) et en milieu non polaire (hexane) aussi bien qu'en milieu polaire (CH2Cl2). Un mecanisme reactionnel a ete propose avec un coamorcage du a l'eau de cristallisation et/ou a l'acide triflique provenant de la synthese du triflate. Il a ete mis en evidence une reaction de transfert au polymere et des reactions de cyclisation intramoleculaire et de reticulation. Une etude de la reactivite des isomeres du pentadiene montre que l'isomere trans est plus reactif que l'isomere cis et ne donne que des enchainements 1,2 et 1,4. Par contre, l'isomere cis peut donner aussi des enchainements 3,4 et a une tendance plus grande a la formation de cycle.