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The article explores the rise of interdisciplinarity in research, emphasizing its effectiveness in addressing complex scientific and societal issues through collaborative efforts. Topics discussed include the integration of diverse disciplines in polymer research, the growing recognition of interdisciplinary approaches in funding and university rankings, and specific examples where interdisciplinary cooperation has led to successful innovations in various fields.

This study explores how the presence of nanofillers with different structural and chemical characteristics, specifically silica nanoparticles and exfoliated graphite nanoplatelets (GNP), alters the crystallization behavior and polymorphism of a semicrystalline polymer, such as polypropylene (PP). The main focus of this research is to investigate how silica and GNP affect the nucleation and growth of PP crystals during isothermal crystallization. The nonisothermal crystallization behavior, including crystal structures, crystallization temperature, and rate, is also determined. PP composites with nanomaterial content up to 7 wt% were produced by melt mixing and injection molding. Both silica and graphite were found to be effective nucleating agents, significantly increasing the crystallization rate during isothermal crystallization, with greater changes observed in case of GNP composites. The effect of filler type and amount on the PP polymorphism and lamella thickness was studied by X-ray diffraction and modulated differential scanning calorimetry. Both silica and graphite were found to be effective nucleating agents for the less common β-phase of PP crystals even at low nanomaterial concentration, α--crystal perfection and the recrystallization of the β-form in the α-form and/ or at the transcrystalline regime were found to be responsible for the recrystallization occurring upon melting in nanocomposites at high silica or medium GNP content. POLYM. ENG. SCI., 55:672-680, 2015. © 2014 Society of Plastics Engineers, INTRODUCTION Isotactic polypropylene (PP) can crystallize in various forms or phases. In particular, depending on the crystallization conditions and molecular characteristics, different packing structures of the PP helices lead to [...]

Poisson's ratio of polymeric materials, although generally assumed as a constant, is known to display a viscoelastic dependence on time, temperature, and strain. This article investigates the phenomenology of this dependence on two crosslinked epoxy systems with different glass transition temperatures. Poisson's ratio measurements are performed by contact extens-ometers simultaneously measuring the axial and trans verse deformations under two different tensile testing conditions: (i) constant deformation rate, in which the effects of strain, strain rate, and temperature are high-lighted; (ii) stress relaxation (or constant deformation), where the dependence of Poisson's ratio on time is studied at various strain levels. The viscoelastic Poisson's ratio increases as strain, temperature, and time increases, with trends markedly depending on the materials glass transition. POLYM. ENG. SCI., 48:1434-1441, 2008. (c] 2008 Society of Plastics Engineers, INTRODUCTION In a deformed solid, Poisson's ratio is defined as the negative ratio between the lateral deformation and the axial imposed deformation. It is defined for infinitesimal extensions, and for [...]

Submicron titania particles were prepared by means of two different synthetic procedures in order to obtain different particle size (diameter ranging from 20 to 350 nm), shapes, and morphologies (amorphous or crystalline). Titania particles were surface modified with octadecylsilane in order to improve their compatibility with respect to polymeric matrices. High-density polyethylene (HDPE)-titania composites were prepared by melt blending by using an internal mixer. The obtained composites were mechanically characterized in quasi static and creep tensile conditions. The presence of submicron titania particles (1%vol) led to a significant increase of elastic modulus (20-25%) with respect to the unreinforced HDPE together with a slight increase of yield stress and a decrease of ultimate elongation. An interesting reduction for both elastic and viscoelastic creep compliance components was also evidenced. POLYM. ENG. SCI., 48:448-457, 2008. © 2008 Society of Plastics Engineers, INTRODUCTION In conventional microparticle-filled composites, a large amount of fillers (>20 vol%) is generally required to appreciably increase the elastic modulus and reduce the creep compliance of thermoplastic matrices [1]. [...]

Viscoelastic behavior of most polymeric materials is nonlinear over a major portion of the interval of their response to external forces. The phenomenological theory of viscoelasticity, based on the assumption that molecular (segmental) motions are controlled by available fractional free volume f, was found adequate for description of the nonlinear tensile creep, implementation of the time-strain superposition and prediction of the nonlinear creep of studied blends. As f of thermoplastics with Poisson's ratio smaller than 0.5 rises proportionally to tensile strain, advancing creep accounts for shortening of retardation times. Consequently, the shift factor along the internal time scale in the time-strain superposition is not constant for a creep curve, but monotonically rises with the elapsed creep time. Compliance curves for various stresses obey fairly well the internal time-strain superposition forming a generalized compliance curve related to an iso-free volume reference state. The predictive format for the blend compliance is based on the parameters characterizing the creep of parent polymers, data on the phase structure of blends obtained from the two-parameter equivalent box model and modified equations of the percolation theory. Applicability of the proposed format is demonstrated on a series of blends of high-density polyethylene with creep-resistant cycloolefin copolymer. POLYM. ENG. SCI., 46:1363-1373, 2006. © 2006 Society of Plastics Engineers, INTRODUCTION Resistance to creep is viewed [1-4] as a significant property of polymeric materials whenever end products are exposed to a more or less constant external force (dead load). As [...]