Polyesters based on 2,5-furandicarboxylic acid (FDCA) are a new class of biobased polymers with enormous interest, both from a scientific and industrial perspective. The commercialization of these polymers is imminent as the pressure for a sustainable economy grows, and extensive worldwide research currently takes place on developing cost-competitive, renewable plastics. The most prevalent method for imparting these polymers with new properties is copolymerization, as many studies have been published over the last few years. This present review aims to summarize the trends in the synthesis of FDCA-based copolymers and to investigate the effectiveness of this approach in transforming them to a more versatile class of materials that could potentially be appropriate for a number of high-end and conventional applications.

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BackgroundThree-dimensional virtual worlds are becoming very popular among educators in the medical field. Virtual clinics and patients are already used for case study and role play in both undergraduate and continuing education levels. Dental education can also take advantage of the virtual world’s pedagogical features in order to give students the opportunity to interact with virtual patients (VPs) and practice in treatment planning.ObjectiveThe objective of this study was to design and evaluate a virtual patient as a supplemental teaching tool for pediatric dentistry.MethodsA child VP, called Erietta, was created by utilizing the programming and building tools that online virtual worlds offer. The case is about an eight-year old girl visiting the dentist with her mother for the first time. Communication techniques such as Tell-Show-Do and parents’ interference management were the basic elements of the educational scenario on which the VP was based. An evaluation of the simulation was made by 103 dental students in their fourth year of study. Two groups were formed: an experimental group which was exposed to the simulation (n=52) and a control group which did not receive the simulation (n=51). At the end, both groups were asked to complete a knowledge questionnaire and the results were compared.ResultsA statistically significant difference between the two groups was found by applying a t test for independent samples (P<.001), showing a positive learning effect from the VP. The majority of the participants evaluated the aspects of the simulation very positively while 69% (36/52) of the simulation group expressed their preference for using this module as an additional teaching tool.ConclusionsThis study demonstrated that a pediatric dentistry VP built in a virtual world offers significant learning potential when used as a supplement to the traditional teaching techniques.

Plastics are perceived as modern and versatile materials, but their use is linked to numerous environmental issues as their production is based on finite raw materials (petroleum or natural gas). Additionally, their low biodegradability results in the accumulation of microplastics. As a result, there is extensive interest in the production of new, environmentally friendly, bio-based and biodegradable polymers. In this context, poly(ethylene vanillate) (PEV) has a great potential as a potentially bio-based alternative to poly(ethylene terephthalate); however, it has not yet been extensively studied. In the present work, the preparation of PEV is reported. The enthalpy and the entropy of fusion of the pure crystalline PEV have been estimated for the first time. Additionally, the equilibrium melting temperature has also been calculated. Furthermore, the isothermal and non-isothermal crystallization behavior are reported in detail, and new insights on the thermal stability and degradation mechanism of PEV are given.

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The relatively new biobased polyester poly(propylene furanoate), PPF, belongs in a class of polymers prepared from renewable resources and expected to replace its fossil-based homologues. Due to its potential in future applications and for the optimization of the material properties such as the mechanical performance, manipulation of crystallinity is crucial, which is rather slow for PPF. By following previous work in semicrystalline polymers, crystallization rate enhancement is achieved here by in situ introduction to the PPF matrix of low amounts, 1 wt %, of carbon nanotubes (CNT) and graphene oxide (GO) platelets. A combination of complementary techniques are employed for this work, which include nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopy for the nanocomposites structure, X-ray diffraction (XRD) for the crystalline structure, differential scanning calorimetry (DSC) for thermal transitions, and broad-band dielectric spectroscopy (BDS) for molecular dynamics. Crystallization is accelerated in the nanocomposites due to the fillers acting as additional crystallization nuclei, whereas the degree of crystallinity is barely enhanced. The latter is correlated with alternations in the semicrystalline morphology (XRD, DSC). Furthermore, we investigate the additional role of surface functionalization of these fillers by proper groups in order to promote the polymer−filler interaction degree. The enhanced interfacial interactions were confirmed by FTIR and the suppressed glass transition strength. Interestingly, this enhancement was found to actually result in a deceleration of crystallization, as the formed interfacial bound polymer fraction does not seem to contribute to crystallization. In general, the effects imposed by the CNTs were stronger as compared to GO, most probably due to the larger aspect ratio of the nanotubes. Regarding molecular mobility, the glass transition was studied in the amorphous and the semicrystalline state. The segmental polymer mobility, calorimetric T g and dynamic α relaxation, is governed in the amorphous state by the low molecular weight (MW ≈ 10k−20k) and, further, by crystallinity. On the other hand, the strength of glass transition is suppressed by the formation of interfacial bound polymer (interactions). Finally, we were able to record the local polymer dynamics below T g (i.e., β relaxation), which seems to be sensitive to structural changes of the matrix, and the global chain dynamics above T g (Normal Mode, NM, relaxation), dependent on the low MW, as expected.