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In recent years, antifouling (AF) polymers are widely used in marine paints to protect the ship hulls from biofouling. The AF polymer coatings have better leaching characteristics and long lasting efficiency than other conventional formulations. In this study, an attempt has been made to prepare new p-acryloyloxybenzaldehyde(AcBA) polymers to assess their AF efficiency against marine microfoulers. The monomer, AcBA was prepared by the esterification reaction between p-hydroxybenzaldehyde (HBA) and acryloyl chloride (Ac) in presence of triethylamine (TEA) in MEK at 0 C. The reaction was monitored by TLC and the prepared monomer was characterized by UV, IR, were prepared by solution polymerization using BPO as initiator. To find out the AF activity of prepared polymers, representatives of marine microfoulers, shipfouling bacteria (Bacillus macroides and Pseudomonas aeruginosa) and microalgae (Amphora coffeaeformis and Navicula incerta) were screened. The contact toxicity and diatom attachment assays were conducted with prepared polymers and microfouling formation on coatings was also investigated using a tubular biofilm reactor. AF potential of these polymers coating is demonstrated.

A new polymer conjugate of poly(ethylene glycol) (PEG) and 10,12-pentacosadiynoic acid (PCDA), PEG-PCDA conjugate, was synthesized by coupling reaction between carboxyl group of PCDA and hydroxyl group of PEG. Luminescent CdSe/ZnS QDs were encapsulated in the polymer micelles of mixtures of PEG-PCDA and PCDA using solid dispersion method to prepare water-soluble and biocompatible QD micelles. Upon UV-irradiation, the core of QD micelles was further stabilized by intramicellar crosslinking between neighboring PCDA moieties. The polymer conjugate was characterized by 1H-NMR, FT-IR, and GPC measurements, and thereof QD micelles observed using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The QD micelles were spherical with diameters in the range of 30-190 nm. The encapsulated QDs in polymer micelles are water-soluble and have the high potential for applications in biomedical imaging and detection due to their good colloidal stability and biocompatible surface.

Long aliphatic chain containing substituted phenols like (9-(2-hydroxy 3,5dinonylphenyl) methyl stearate (DNPMS), (9-(2-hydroxy 3,5-dicumyl phenyl) methyl stearate (DCPMS) and (9-(4-hydroxy 3,5-ditertiary butyl phenyl) methyl stearate (DTBPMS) have been prepared by Friedel Crafts alkylation of hindered phenols such as 2,4-dinonyl phenol (DNP), 2,4-dicumyl phenol (DCP) and 2,6ditertiary butyl phenol (DTBP) respectively with methyl oleate in presence of AlCl 3 at room temperature. To study the effi cacy of these compounds as antioxidants, natural rubber mixtures have been prepared. The physical and mechanical properties of the rubbers were determined. The effects of the prepared compounds on the mechanical properties after ageing were evaluated. It was found that the synthesized compounds showed good antioxidant behaviour compared with the industrially used conventional antioxidant styrenated phenol (SP). In the second part, we have studied the effect of antioxidant DTBPMS which is having structural similarity with Irganox 1076, on the ageing of NR-SBR blend vulcanizates Hawai footwear application. It was found that the DTBPMS showed delayed initial crack formation and other mechanical properties were comparable to those of vulcanizates containing Irganox 1076.