Valorization of poly(lactic acid) wastes via mechanical recycling: Improvement of the properties of the recycled polymer.

Poly(lactic acid) (PLA) is a biobased polymer that represents one of the most interesting alternatives to fossil-fuel based polymers in food packaging applications. Most of the PLA used in food packaging is used only once and then discarded, even though the PLA types used in packaging have good properties and stability. Therefore, it seems reasonable to consider the possibility of recycling the used polymer through a mechanical recycling process. The main aims of this work are to study the effect of the mechanical recycling on the properties of PLA and the usefulness of different upgrading methods to obtain recycled PLA with improved properties. A commercial type of PLA was subjected to accelerated thermal, photochemical and hydrolytic aging and then reprocessed. During reprocessing, aged PLA was blended with virgin PLA and a commercial chain extender was added. Results point out that recycling causes the degradation of PLA, and negatively affects the thermal stability and mechanical properties. However, addition of virgin PLA, and the chain extender, led to an increase of up to 9% in the intrinsic viscosity and 8% in the Vickers hardness of the recycled material. These results suggest that mechanically recycled PLA with improved performance can be obtained, a fact which might improve the recyclability of PLA and thus the environmental impact of this material.

Effect of simulated mechanical recycling processes on the structure and properties of poly(lactic acid).

The aim of this work is to study the effects of different simulated mechanical recycling processes on the structure and properties of PLA. A commercial grade of PLA was melt compounded and compression molded, then subjected to two different recycling processes. The first recycling process consisted of an accelerated ageing and a second melt processing step, while the other recycling process included an accelerated ageing, a demanding washing process and a second melt processing step. The intrinsic viscosity measurements indicate that both recycling processes produce a degradation in PLA, which is more pronounced in the sample subjected to the washing process. DSC results suggest an increase in the mobility of the polymer chains in the recycled materials; however the degree of crystallinity of PLA seems unchanged. The optical, mechanical and gas barrier properties of PLA do not seem to be largely affected by the degradation suffered during the different recycling processes. These results suggest that, despite the degradation of PLA, the impact of the different simulated mechanical recycling processes on the final properties is limited. Thus, the potential use of recycled PLA in packaging applications is not jeopardized.

Healthcare utilisation in patients with breast cancer or non-Hodgkin lymphoma who experienced febrile neutropenia in the Netherlands: a retrospective matched control study using the PHARMO database.

Few data have been published on healthcare resource utilisation associated with chemotherapy-induced febrile neutropenia (FN) in Europe. Using the PHARMO record linkage system, we identified incident adult patients with a primary hospital discharge diagnosis of breast cancer (BC) or non-Hodgkin lymphoma (NHL) from 1998 to 2008. Patients who experienced FN were matched 1:2 non-FN reference patients. Of 1033 BC patients, 80 (8%) had FN and were matched with 160 reference patients; and of 486 NHL patients, 95 (20%) had FN and 89 were matched with 178 reference patients. Significantly more FN patients were hospitalised for any cause than reference patients: BC, 81% vs. 24% (OR 12.6; 95% CI 5.7-27.8); NHL, 82% vs. 44% (OR 6.7; 95% CI 3.3-13.9). Median length of all-cause hospitalisation stay was higher for FN patients: BC, 4.0 vs. 1.0 days; NHL, 8.5 vs. 1.8 days. The median (interquartile range) number of medication treatments was higher for FN patients: BC, 5.5 (4.0-7.5) vs. 2.0 (2.0-4.0); NHL, 8.0 (5.0-11.0) vs. 3.0 (2.0-4.0). In conclusion, FN in patients with BC or NHL had increased healthcare utilisation compared with non-FN patients; thus, efforts to reduce FN are warranted to reduce cost and improve outcomes.

Cost-effectiveness of erlotinib versus docetaxel for second-line treatment of advanced non-small-cell lung cancer in the United Kingdom.

This study was designed to assess the cost-effectiveness of erlotinib compared with docetaxel in the second-line management of advanced non-small-cell lung cancer (NSCLC) within the UK National Health Service (NHS). A health-state transition model, based on two randomized phase III studies of erlotinib or docetaxel versus best supportive care, was used to estimate total direct costs, quality-adjusted life years (QALYs) and the subsequent net monetary benefit. Erlotinib was associated with a reduction in total costs ( pound13 730 versus pound13 956) and improved outcomes (total QALYs of 0.238 versus 0.206) compared with docetaxel. Sensitivity analyses demonstrated the robustness of this analysis. In summary, erlotinib appeared to generate similar overall survival, an increase in QALYs and a small reduction in total NHS costs compared with docetaxel, due to lower adverse event and drug administration costs. Consequently, from a health economics perspective for the treatment of relapsed stage III - IV NSCLC patients in the UK, erlotinib has advantages over docetaxel.

Study of the effects of the reaction conditions on the modification of clays with polyelectrolytes and silanes.

New organically modified clays have been obtained from sodium montmorillonite, using either a cationic polyelectrolyte (polyethylenimine) or a novel homemade bisphenol-A silane as modifiers. The modification processes have been carried out in different reaction media, in order to study the effects on the properties of the modified clays of several reaction parameters, such as the pH of the polyethylenimine solution or the nature of the solvent used in the silanization. The obtained clays were characterized using X-ray diffraction, thermogravimetric analysis, and FTIR spectroscopy. Clays modified with polyelectrolyte or silane show significant increases in the basal spacing. The properties of polyelectrolyte-modified clays depend on the pH of the treating solution. The increase in the basal spacing of polyelectrolyte-modified clays varies only slightly with the pH; however, this reaction parameter clearly determines the total amount of polyelectrolyte introduced in the clay. The properties and applications of silane-modified clays are strongly dependent on the presence of water in the reaction media used for the silanization. These results have been explained by considering that the reaction conditions determine the nature and the amount of material intercalated into the clay.