Dataset Information

Improving Interaction at Polymer-Filler Interface: The Efficacy of Wrinkle Texture.

ABSTRACT: One of the main issues in preparing polymer-based nanocomposites with effective properties is to achieve a good dispersion of the nanoparticles into the matrix. Chemical interfacial modifications by specific coupling agents represents a good way to reach this objective. Actually, time consuming compatibilization procedures strongly compromise the sustainability of these strategies. In this study, the role of particles' architectures in their dispersion into a poly-lactic acid matrix and their subsequent influences on physical-chemical properties of the obtained nanocomposites were investigated. Two kinds of silica nanoparticles, "smooth" and "wrinkled," with different surface areas (≈30 and ≈600 m2/g respectively) were synthesized through a modified Stöber method and used, without any chemical surface pre-treatments, as fillers to produce poly-lactic acid based nanocomposites. The key role played by wrinkled texture in modifying the physical interaction at the polymer-filler interface and in driving composite properties, was investigated and reflected in the final bulk properties. Detailed investigations revealed the presence of wrinkled nanoparticles, leading to (i) an enormous increase of the chain relaxation time, by almost 30 times compared to the neat PLA matrix; (ii) intensification of the shear-thinning behavior at low shear-rates; and (iii) slightly slower thermal degradation of polylactic acid.

SUBMITTER: Russo P

PROVIDER: S-EPMC7074972 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:IntroductionPolymer materials used in medical devices and treatments invariably encounter cellular networks. For the device to succeed in tissue engineering applications, the polymer must promote cellular interactions through adhesion and proliferation. To predict how a polymer will behave in vitro, these material-cell interactions need to be well understood.MethodsTo study polymer structure-property relationships, microparticles of four chemically distinct tyrosol-derived poly(ester-arylate) polymers and a commercially available poly(lactic acid-co-glycolic acid) (PLGA) copolymer were prepared and their interactions with cells investigated. Cell loading concentration was optimized and cell adhesion and proliferation evaluated. Particles were also tested for their ability to adsorb bone morphogenetic protein-2 (BMP-2) and differentiate a myoblast cell line towards an osteoblast lineage through BMP-2 loading and release.ResultsWhile cell adhesion was observed on all particles after 24 h of incubation, the highest degree of cell adhesion occurred on polymers with smaller crystallites. At longer incubation times, cells proliferated on all particle formulations, regardless of the differences in polymer properties. High BMP-2 loading was achieved for all particle formulations and all formulations showed a burst release. Even with the burst release, cells cultured on all formulations showed an upregulation in alkaline phosphatase (ALP) activity, a measure of osteoblast differentiation.ConclusionsAs with cell adhesion, the polymer with the smaller crystallite showed the most ALP activity. We suggest that smaller crystallites serve as a proxy for topographical roughness to elicit the observed responses from cells. Furthermore, we have drawn a correlation between the polymer crystallite with the hydration potential using surface analysis techniques.Graphical abstractSupplementary informationThe online version contains supplementary material available at 10.1007/s12195-022-00729-9.

Project description:In recent years, an increasing number of polymeric composites incorporating engineered nanomaterials (ENMs) have reached the market. Such nano-enabled products (NEPs) present enhanced performance through improved mechanical, thermal, UV protection, electrical, and gas barrier properties. However, little is known about how environmental weathering impacts ENM release, especially for high-tonnage NEPs like kaolin products, which have not been extensively examined by the scientific community. Here we study the simulated environmental weathering of different polymeric nanocomposites (epoxy, polyamide, polypropylene) filled with organic (multiwalled carbon nanotube, graphene, carbon black) and inorganic (WS2, SiO2, kaolin, Fe2O3, Cu-phthalocyanines) ENMs. Multiple techniques were employed by researchers at three laboratories to extensively evaluate the effect of weathering: ultraviolet-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), optical microscopy, contact angle measurements, gravimetric analysis, analytical ultracentrifugation (AUC), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Raman spectroscopy. This work aimed to elucidate the extent to which weathering protocol (i.e. wet vs. dry) and diverse filler characteristics modulate fragment release and polymer matrix degradation. In doing so, it expanded the established NanoRelease protocol, previously used for analyzing fragment emission, by evaluating two significant additions: (1) simulated weathering with rain events and (2) fractionation of sample leachate prior to analysis. Comparing different composite materials and protocols demonstrated that the polymer matrix is the most significant factor in NEP aging. Wet weathering is more realistic than dry weathering, but dry weathering seems to provide a more controlled release of material over wet. Wet weathering studies could be complicated by leaching, and the addition of a fractionation step can improve the quality of UV-vis measurements.

Dataset Information

Improving Interaction at Polymer-Filler Interface: The Efficacy of Wrinkle Texture.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets