Influence of the Organoclay Content on the Structure, Morphology, and Surface Related Properties of Novel Poly(dimethylsiloxane)-Based Polyurethane/Organoclay Nanocomposites

Abstract

Novel poly(dimethylsiloxane)-based polyurethane nanocomposites (TPU-NCs) were synthesized using in situ polymerization with the nanoclay, Cloisite 30B. DSC, TGA and DMTA analyses showed that TPU-NCs with organoclay content ≤5 wt % exhibited increased thermal stability, storage modulus and hard segment melt temperatures, but decreased degrees of crystallinity. TPU-NCs displayed increased surface hydrophilicity and enhanced surface free energy with increasing organoclay content. SWAXS confirmed intercalated formations of organoclays in the nanocomposites. Individual clay particles on surfaces of TPUs with lower organoclay loadings (1 or 3wt %), or organoclay agglomerates in TPUs with higher amounts of organoclay (≥ 5 wt %) were detectable using SEM. The relatively smooth and homogeneous character of pure TPU and the distinctly heterogeneous and rough surfaces of TPU-NCs were detected via AFM. Among the nanomaterials prepared, TPU-NC with 1 wt % of organoclay provided the best balance between organoclay concentration and the functional properties desired in biomedical applications.

Surface Characterization and Anti-Biofilm Effectiveness of Hybrid Films of Polyurethane Functionalized with Saponite and Phloxine B

“…The PUC samples exhibited lower values (p-value < 0.001). The high contact angle of water on the PU membrane would indicate the hydrophobic properties of this polymer which is in agreement with some other studies [36,37]. A relatively high CH 2 I 2 contact angle indicates that the PU membrane is not a typical hydrophobic material.…”

“…A thin layer of OC coming into contact with the liquid precursor efficiently adsorbed water together with other volatile compounds, which prevented the formation of microcavities on the surface of a composite. Similar changes were observed for PU composites with present OC in another study reporting the reduction of contact angles for water, as well as non-polar solvents [37]. The trends of increasing energies with dispersed OC were observed also for other polymers.…”

Highly exfoliated montmorillonite clay reinforced thermoplastic polyurethane elastomer:in situpreparation and efficient strengthening

“…25 This phenomenon may be caused from better directionally orientation of TPU chains and enhancement of melt crystallization aer importation of the exfoliated MMT layers and TPU matrix. 29 3.4. Mechanical properties of TPU nanocomposites 3.4.1.…”

“…[14][15][16][17][18][19][20] Numerous literatures on TPU nanocomposites pay great attention on the effect of methods of preparation, structure of polyurethane, microphase morphology, rheology, mechanical properties, thermal stability, etc. [21][22][23][24][25][26][27][28][29][30][31][32] Wang et al 33 rst reported the preparation of the polyurethane (PU)/clay nanocomposites, and concluded that large enhancements in tensile strength and modulus were possible even with intercalated clay particles. To take full advantage of these nanoscale MMT sheets, the key is to exfoliate and disperse the individual MMT layers within polymer matrices, which requires favorable organically modied MMT particles (OMMTs) interactions according to the thermodynamic theory.…”

Physicochemical characteristics of bio‐based thermoplastic polyurethane/graphene nanocomposite for piezoresistive strain sensor

“…The nanocomposite did not show any aggregation of graphene suggesting homogenous dispersion within the matrix. [ 38–40 ] However, TPU‐2.0 showed some bright spots on the surface, which could be graphene nanoplatelets either dispersed or aggregated nanoplatelets. From the EDS analysis, upon increasing the graphene loading the carbon content and oxygen content increased.…”