The effects of hypochlorite level, i.e. 0.5; 1 and 2 active chlorine g/100g starch, on the properties of oxidized maize starch were investigated by FT-IR and solubility of oxidized starch and starch film. The obtained results shown that there was no difference of IR spectroscopy graph between native starch and oxidized starch. Although the analytical results indicated that there were carbonyl and carboxyl production, characteristic vibrations of these groups exhibiting on IR spectra was not clear due to either not enough content of carbonyl and carboxyl groups or covering of strong other absorptions. Notwithstanding, IR spectra also shown the change of intensity of characteristic vibrations. Moreover, solubility of starch oxidized by the highest oxidant content level experienced highest degree while solubility of this starch shown the lowest level. It means that carboxyl in this molecule starch, to some extent, esterified with hydroxyl of either other starch molecules or glycerol to produce crosslink. The obtained results also illustrated that there was a little scission chain in oxidation process when modifying maize starch by sodium hypochlorite.

The effect of polyamine having molecular weight 70,000u (BT70) in the non-cyanide alkaline plating bath on the morphological zinc electrodeposited coating was investigated. The obtained results from the reflectance of electrodeposited zinc coating by a suitable range of electro-current density and SEM images showed that BT70 had effect on the zinc plating in comparison with the zinc deposits from plating bath without BT70. The electrodeposited coating surface was rough and poor adhesion. However, adding BT70 into the plating bath led to the surface roughness of electrodeposited coating and grand size being reduced. Zinc electrodeposited coating from a plating bath containing BT70 at 0.5 g/L, respectively, experienced the highest reflectance, equal 46 % of the electrodeposited coating from the bath containing commercial additives. Hull method showed that the zinc deposited coating surface became smoother with the presence of polyamine in non-cyanide alkaline zinc plating solution. The zinc deposited coating had a semigloss scope at 10 A/dm 2. If the BT70 content increased, the semi-gloss scop and the gloss of samples' surfaces also grew up.

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The effects of hypochlorite level, i.e. 0.5; 1 and 2 active chlorine g/100g starch, on the structures and physicochemical properties of oxidized maize starch were investigated. The obtained results shown that oxidation degree grew up with increasing hypochlorite concentration, specially, the carboxyl content saw higher increased than the content of carbonyl. SEM images indicated that surface of oxidized maize starches were rougher than native starch. The surface of oxidized starches saw rougher with increasing hypochlorite level. However, the DSC results illustrated that there was no significant difference of gelatinization temperature between the native starch and oxidized starches.

The effects of the number of substituents and molecular weight of polyamines in the non-cyanide alkaline plating bath on the morphology, brightness and bright ranges of zinc electrodeposited coating and cathodic polarization, cyclic voltammogram on the non-cyanide alkaline zinc plating process were investigated. Cathodic polarization measurements showed that the polyamines all increased cathodic polarization of the plating process and shifted the zinc reduced potential to a more negative direction. However, cycle voltammogram curves of the 5 continuous cycles shows that the quaternary polyamine Q7-20 has a more stable adsorption and desorption processes than the secondary polyamine Bt18 has.