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Blends of low density polyethylene (LDPE) and polyamide 6 (PA6), compatibilized with an ethylene-acrylic acid copolymer (EAA), either alone or combined with a low molar mass bis-oxazoline compound (PBO), have been processed in film blowing operations and the properties of the films have been investigated. Without of compatibilization, the filmability of the blend was very poor and no significant specimen was collected. As a result of the reactive compatibilization, the blends with EAA and even more with the EAA-PBO, were processed successfully in film blowing. The films of the quaternary blends were shown to possess satisfactory mechanical properties as a result of fine and stable morphology. The results confirm the conclusion of a previous study, i.e., that the PBO fourth component may promote the in situ formation of PA6-g-EAA copolymers by reaction with both the functional groups of PA6 and the carboxyl groups of EAA.

New organotin(IV) complexes of 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) and 5,7-diphenyl-1,2,4-triazolo [1,5-a]pyrimidine (dptp) with 1:1 and/or 1:2 stoichiometry were synthesized and investigated by X-ray diffraction, Sn Mössbauer in the solid state and by 1 H and 13 C NMR spectroscopy, in solution. Moreover, the crystal and molecular structures of Et 2 SnCl 2 (dbtp) 2 and Ph 2 SnCl 2 (EtOH) 2 (dptp) 2 are reported. The complexes contain hexacoordinated tin atoms: in Et 2 SnCl 2 (dbtp) 2 two 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine molecules coordinate classically the tin atom through N(3) atom and the coordination around the tin atom shows a skew trapezoidal structure with axial ethyl groups. In Ph 2 SnCl 2 (EtOH) 2 (dptp) 2 two ethanol molecules coordinate tin through the oxygen atom and the 5,7-diphenyl-1,2,4-triazolo [1,5-a]pyrimidine molecules are not directly bound to the metal center but strictly H-bonded, through N (3), to the \OH group of the ethanol moieties; Ph 2 SnCl 2 (EtOH) 2 (dptp) 2 has an all-trans structure and the C-Sn-C fragment is linear. On the basis of Mössbauer data, the 1:2 diorganotin(IV) complexes are advanced to have the same structure of Et 2 SnCl 2 (dbtp) 2 , while Me 2 SnCl 2 (dptp) 2 to have a regular all-trans octahedral structure. A distorted cis-R 2 trigonal bipyramidal structure is assigned to 1:1 diorganotin(IV) complexes. The in vitro antibacterial activities of the synthesized complexes have been tested against a group of reference pathogen micro-organisms and some of them resulted active with MIC values of 5 μg/mL, most of all against staphylococcal strains, which shows their inhibitory effect.

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An ethylene‐acrylic acid copolymer (EAA), either alone or combined with a low molar mass bis‐oxazoline compound (PBO), has been used as a compatibilization promoter for blends of polyamide‐6 (PA6) with low‐density polyethylene (LDPE). The effect of compatibilization on blend processability in injection molding operations and on the properties of the molded specimens has been studied. In the absence of compatibilization, the injection molded articles were shown to have low‐quality surface appearance and poor mechanical properties. Both these characteristics were appreciably improved as a result of reactive compatibilization of the blends with EAA and, even more, with the EAA‐PBO couple. In fact, the finished articles prepared by injection molding of the quaternary blends were shown to possess good surface appearance, fine and stable morphology and satisfactory mechanical properties. The results confirm the conclusion of a previous study, i.e., that the PBO fourth component may promote the in situ formation of PA6‐g‐EAA copolymers, by reaction with both the functional groups of PA6 and the carboxyl groups of EAA. Polym. Eng. Sci. 44:1732–1737, 2004. © 2004 Society of Plastics Engineers.