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COI Lab Analysis

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An increase in PCL triol content caused an increase in the relative intensity of the symmetric deformation of CH2 groups of PU films, observed in the range of 1475 – 1450 cm-1. Also, the symmetric stretching of N-COO and stretching of C-O-C bond in polyurethane are observed in the range of 1150 – 940 cm-1. A reduction in the relative intensity of the main PU absorbance peaks was observed in the samples after ultrasonic process, whereas the broad band in the region of 1100 – 1000 cm-1 maintained its intensity even after ultrasonic process. This region is often related to the Si-O-Si asymmetric stretching in bioactive glasses, and may be overlapping C-O-C absorption region of the PU. P-O stretching in bioactive glasses is often assigned to …show more content…

The final size depends on the balance between the nucleation and aggregation rates in the system. Fig. 2 (g) and (h) presented the EDS analysis on treated samples, confirming the presence of Silica, Calcium and Phosphorous from the bioactive glass on the surface of the modified films. Degradation assay. The hydrolytic degradation plays an important role in the biomaterials development. In ester-based polymer, this process usually involves three stages: (i) incubation stage, in which water absorption occurs; (ii) induction stage, during which polymer chain is broken via ester bonds; (iii) erosion, the final stage, wherein the water-soluble entities (for example PEG blocks and oligomers) are dissolved in the buffer solution, resulting in a polymer mass loss [22]. Therefore, the SBF assay was performed in order to evaluate the weight loss related to the degradation of polyurethane samples. Fig. 3 presents the weight loss of the samples after 7, 14, 21, 28 and 90 days of immersion in SBF solution at 37 ºC. After 90 days, the remaining mass obtained was 90.0 ± 2.7 % for PU3, 87.8 ± 2.6 % for PU12, 89.3 ± 1.3 % for PU3VB and 86.9 ± 1.1 % for PU12VB. The degradation pattern of samples with and without bioactive glass was quite similar, especially for the first 28 days of

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