Analysis of interactions in multicomponent polymeric systems: The key-role of inverse gas chromatography

doi:10.1016/j.mser.2005.07.003

Materials Science and Engineering: R: Reports

Volume 50, Issue 3, 31 October 2005, Pages 79-107

https://doi.org/10.1016/j.mser.2005.07.003 Get rights and content

Abstract

The properties of a polymeric system are a consequence of the interactions that occur between the various components of these complex systems. These components may vary significantly in terms of chemical nature (e.g. organic/inorganic), physical properties (e.g. particle size, surface area, molecular weight), structural characteristics and proportion in the formulations composition. This review paper addresses the major approaches in use regarding the analysis of the interactions that occur between the polymeric system components and the use of such approaches in the interpretation of the chemical, physical and thermodynamic properties of these systems. Special attention is given to the technique of inverse gas chromatography.

A case study is presented, where use was made of inverse gas chromatography to characterize thermodynamically the surface of the major components of pigmented PC/PBT blends. The concept of Lewis acidity/basicity was used in the interpretation of the intermolecular interactions nature and potential in these blends, as encountered in phase separation and phase preferences phenomena and as expressed in the morphology, the physical and the mechanical properties of these commercially important composites.

Introduction

The strong correlations that exist between the morphology, the processing and the physical and the mechanical properties in multicomponent polymeric systems are well-recognised [1], [2]. These aspects and correlations are a consequence of the interactions that occur between the various components of polymer-based systems. As the number of constituents in these systems increases, the ways in which the various components interact and become dispersed/segregated during processing and in service, become increasingly important. Among these added materials are the stabilisers, plasticizers, reinforcing fibres, pigments and other polymers.

In the particular case of polymer mixtures, the morphologies of two-component polymer blends have been widely discussed in the literature as these represent the more common commercial form of polymer blends. In response to commercial pressures and to the need for precisely tailored physical properties, more complex blends that consist of multiple components are under active development. In such blends, morphological concerns go beyond questions concerned with the dispersed phase size, anisotropy, etc., to include other issues, such as why one of the dispersed polymer phases may spontaneously encapsulate another [3] or encapsulate the filler particles [4]. Obviously, in multiphase polymer systems, interfaces and interphases must exit. Therefore, it is reasonable to assume that under equilibrium conditions, such effects must arise from interfacial energy differences among the blend components. Surface and interfacial phenomena have been proven to influence:

(i)
the dispersion of minor phases in polymer matrices [5], [6];
(ii)
the processability of polymer blends and composites [7], [8];
(iii)
the mechanical properties of polymer blends [9], [10].

Moreover, it is well-known that, for polymer blends, the apparent properties and morphology often do not indicate an equilibrium situation [11]. For instance, in blends of an amorphous polymer and a semi-crystalline polymer, the phase behaviour is strongly dependent on blending and the cooling conditions. In the case of partial miscibility or of complete miscibility of the components in the molten state, the cooling rate and the kinetics of non-isothermal crystallisation influence the final extent of phase separation at room temperature. The attainment of the thermodynamic equilibrium is determined by the nature and magnitude of the interactions between the components of these systems, as reflected in the existence of intermolecular forces.

The use properties of polymer blends depend strongly on the miscibility (compatibility) of the polymers. Miscibility occurs when specific interaction forces develop between the two (at least) polymers [12], [13]. Specific interactions may be in the form of hydrogen bonding, charge transfer complexes, acid–base type interactions, dipole moments and electron donor–acceptor complexes [14], [15], [16], [17], [18]. These specific interactions are of a highly directional nature and are present in addition to the dispersive forces. A current view, pioneered by Fowkes [14], [19], [20], [21], [22], [23], [24], [25], which is increasingly accepted, suggests that the totality of specific interactions may be viewed as Lewis acid–base forces. This approach has been supported by experimental results [24].

Intermolecular forces that are operating between molecular segments of polymers and at particulate interfaces are frequently cited in the literature [3], [26], [27], [28], [29], [30], [31], [32], [33], [34], [35] as being responsible for the properties of the system as a whole. In the particular case of polymer nanocomposites, e.g. polymeric matrices filled with well-dispersed, high shape-factor nanofillers, the self-organisation of the polymer chains has been reported to be significantly influenced by the nature and magnitude of the intermolecular interactions between the inorganic and the polymeric components. For instance, in polyamide (e.g. Nylon-6) matrices filled with organoclays, important changes in the crystallisation behaviour of this polymer have been reported [36], [37], [38], [39].

Control of Lewis acid–base (specific) interactions has gained increasing significance in industrial practice for optimising the performance of polymer composites [14], [40], [41]. This is because such intermolecular forces are known to dominate over dispersion intermolecular forces and dipole–dipole intermolecular forces [2], [5], [12], [13], [14], [16], [31], [34], [35], [40], [41], [42], [43], [44]. This is clear in the definition of specific interactions, given by Huyskens et al. [16], “specific interactions are short-range, site-bounded cohesion forces that considerably weaken a given chemical bond of one of the partners”. Furthermore, from a thermodynamic point of view, specific interactions between chemical moieties are required in order to obtain a negative excess free energy by mixing [45].

From the above description, it is clear that there is a link between component interactions on the one hand and the rheological, physico-chemical and mechanical properties of the system, on the other.

Section snippets

Thermodynamic requirements for miscibility in multicomponent polymeric systems

The basic question when considering a multicomponent polymeric system concerns the extent of thermodynamic miscibility. Several polymer pairs are known to be miscible or partially miscible and many of these have become commercially important [2]. Considerable attention has been given to the origins of miscibility and to binary polymer–polymer phase diagrams. It is usually observed that high molar mass polymer pairs, showing partial miscibility, exhibit phase diagrams that indicate a lower

The solubility parameter

One widely used approach to the quantification of interactions that occur in multicomponent polymeric systems is through the determination of “solubility” or “cohesion” parameters, δ_T. This parameter is, in effect, the square root of a cohesive energy density, as defined by Hildebrand in Eq. (3) [51], [52], [53]: $δ_{T} = {(\frac{Δ H_{v}}{V})}^{1 / 2}$

Here, ΔH_v is the molar vaporisation energy of the substance and V is its molar volume.

The solubility parameter was originally intended to be applied to substances whose

Interaction parameters from polymer solution theories

Polymer solution thermodynamics, as developed firstly by Flory and Huggins (cited in refs. [56], [57], [58], [59], [60]), expresses the interaction between a polymer and a liquid in terms of a dimensionless parameter, χ_1,2. This can be written as Eq. (4): $χ_{1, 2} = \frac{μ_{1} - μ_{2}}{R T φ_{1}^{2}} - (\ln φ_{1} + (1 - \frac{V_{1}}{V_{2}}) φ_{2}) φ_{2}$

The subscripts 1 and 2 denote the liquid (solvent) and the polymer (solute), respectively, μ the chemical potential, φ the volume fractions and V denotes molar volumes. Miscibility occurs when χ_1,2 is lower than

Work of adhesion and interfacial tension

Researchers, such as Raetzsch et al. [9] and Liang et al. [24] studied miscibility phenomena of polymer blends based on the presence of interfaces in multiphase polymer mixtures, employing the thermodynamic work of adhesion between two different solids and interfacial tension determinations. This specific thermodynamic adhesion energy (W_a) or, in the case of a known adhesion distance, the specific adhesion strength between two solids, can be determined from the respective surface tensions, γ₁

Introduction to inverse gas chromatography (IGC)

The growing awareness of the importance of solid surfaces, interfaces and interphases in determining the useful properties of polymeric systems, has led to the development of inverse gas chromatography as a useful technique in evaluating the potential for interaction of different components of polymer blends, composites and multicomponent polymeric systems. Data obtained from IGC experiments may, in favourable cases, correlate directly with observed performance criteria, such as colour

Conclusions

The intermolecular forces operating in multicomponent polymeric systems contribute decisively to the useful properties of these systems. Several approaches exist that allow for an interpretation, forecast and optimisation of the interactions occurring in such complex systems. These include the use of solubility parameters, of interaction parameters from polymer solution theories, of the concept of work of adhesion and interfacial tension and of diverse thermodynamic parameters and

References (159)

K. Premphet et al.
Polymer
(2000)
F.M. Fowkes et al.
J. Non Cryst. Solids
(1990)
M. Alexandre et al.
Mater. Sci. Eng. R. Rep.
(2000)
T.D. Fornes et al.
Polymer
(2003)
M.H. Lee et al.
Polymer
(2001)
S.Y. Hobbs et al.
Polymer
(1988)
E. Brendle et al.
J. Colloid Interface Sci.
(1997)
J.M.R.C.A. Santos et al.
J. Chromatogr. A
(2002)
R.A.L. Jones et al.
Polymer
(1993)
E. Brendle et al.
J. Colloid Interface Sci.
(1997)

G. Sadowski et al.

Fluid Phase Equilib.

(1997)

E. Papirer et al.

J. Colloid Interface Sci.

(1991)

Y.J. Lee et al.

Powder Technol.

(1992)

A.M. Farooque et al.

Polymer

(1992)

A.J. Ryan

Nat. Mater.

(2002)

L.A. Utracki, D.J. Walsh, R.A. Weiss (Eds.), Multiphase Polymers: Blends and Ionomers, A.C.S., 1989, pp....

H.P. Schreiber et al.

J. Adhes. Sci. Technol.

(1990)

M.Y. Boluk et al.

Polym. Composites

(1986)

M.Y. Boluk et al.

Polym. Composites

(1989)

T.M. Malik et al.

Polym. Composites

(1988)

E. Trujillo et al.

Polym. Composites

(1988)

M. Ratzsch et al.

J. Macromol. Sci. A Chem.

(1990)

H. Ishida

Polym. Composites

(1984)

H.P. Schreiber

M.M. Coleman et al.

Specific Interactions and the Miscibility of Polymer Blends

(1991)

Z.Y. Al Saigh et al.

Macromolecules

(1991)

J. Lara et al.

J. Coat. Technol.

(1991)

V. Ponec et al.

Adsorption on Solids

(1974)

P.L. Huyskens et al.

Intermolecular Forces: An Introduction to Modern Methods and Results

(1991)

J.N. Israelachvili

Intermolecular and Surface Forces

(1991)

A.J. Stone, The Theory of Intermolecular Forces, Claredon Press,...

F.M. Fowkes et al.

Ind. Eng. Prod. Res. Dev.

(1978)

F.M. Fowkes

Rubber Chem. Technol.

(1983)

F.M. Fowkes

J. Adhes. Sci. Technol.

(1990)

H. Liang et al.

J. Polym. Sci. B Polym. Phys.

(2000)

M. Nardin et al.

Composite Interfaces

(1993)

W.B. Jensen

L.H. Lee

F.M. Fowkes

D.W. Dwight et al.

M.F. Finlayson et al.

A.C. Tiburcio et al.

D. Ma et al.

Y.C. Huang et al.

H.P. Schreiber et al.

N. Shenga et al.

Polymer

(2004)

K. Hedicke, H. Wittich, C. Mehler, F. Gruber, V. Altstadt, Composites Sci. Technol., in...

P. Mukhopadhyay et al.

Macromolecules

(1993)

Cited by (111)

Exploring advanced materials: Harnessing the synergy of inverse gas chromatography and artificial vision intelligence
2024, TrAC - Trends in Analytical Chemistry
Inverse gas chromatography (IGC) has emerged as a highly sensitive, adaptable, and effective technology for material analysis. Through employing thermochemical approaches, IGC provides crucial insight into physicochemical information of materials such as dispersive surface free energy, Gibbs surface energy components and Guttamann Lewis acid-base parameters. In this comprehensive review, we delve into the historical background, instrumentation, and diverse applications of IGC. Researchers and practitioners will find valuable information on the selection and description of numerous models used in IGC experiments. The applications of IGC span various domains, including polymers, medicines, minerals, surfactants, and nanomaterials. Furthermore, IGC facilitates the measurement of important parameters such as sorption enthalpy and entropy, surface energy components (dispersive and specific), co/adhesion work, glass transition temperature, surface heterogeneity, miscibility, solubility parameters, and specific surface area. These insights contribute to a deeper understanding of material behavior and aid in the design and optimization of advanced materials. Moreover, the integration of computer vision and image processing techniques with IGC has enhanced our understanding of materials intricate surface texture, roughness, and related properties. This convergence of IGC with computer vision and artificial intelligence (AI) presents exciting opportunities for future exploration of chemical materials, opening new avenues for research and discovery. This paper not only provides a comprehensive overview of IGC, its techniques, and applications but also highlights the synergistic potential of combining IGC with AI and computer vision. The informative content and insights presented here will benefit researchers, scientists, and professionals in the field of advanced materials, enabling them to leverage IGC and AI for innovative materials discovery and development.
Surface energetics and surface chemistry of chicken feather mat for oil spill cleanup application
2024, Journal of Industrial and Engineering Chemistry
This study was conducted to determine the potential of chicken feather mat (CFM), a new biosorbent for oil spill cleanup operations. The surface properties of the CFM in motor oil were determined using Inverse-Gas Chromatography Surface Energy Analyzer and compared to those of polypropylene pad (a conventional sorbent) subjected to the same treatment. The surface properties determined were the Brunauer-Emmett-Teller specific surface area (BET-SSA), dispersive and specific (acid-base) surface energies, specific free energies of adsorption and acid-base numbers, and thermodynamic work of cohesion and adhesion. Results showed that the BET-SSA of the CFM in motor oil (13.67 m²/g) was higher than that of polypropylene pad in motor oil (8.03 m²/g). Additionally, the results of the dispersive and specific (acid-base) surface energies, specific free energies of adsorption and acid-base numbers, and thermodynamic work of cohesion and adhesion show that the CFM is as hydrophobic and oleophilic as the polypropylene pad, suggesting that the CFM is as good as the polypropylene pad in terms of oil sorption. Thus, CFM, an agrowaste, has the potential to be used as a biosorbent for oil spill cleanup operations.
Thermal modeling for anionic surfactant using Inverse gas chromatography and image processing techniques
2023, Journal of Molecular Liquids
Anionic surfactants are one of the necessary ingredients demanded in extensive bio-and pharmaceutical industry. Their concern on human health and environmental safety get increase and is originated from its surface thermodynamic properties. Surface thermodynamic properties have severely an effect on thermodynamic and kinetic parameters in the chemical reaction. However, there is a kind of serious differences between theoretical calculation and experimental result because of lacks of understanding on complex surface thermodynamic properties. Inverse gas chromatography (IGC) is an analytic chemistry tool providing information on physicochemical and thermodynamic parameters. Herein, a thermal modeling of surface thermodynamic properties is suggested. Net retention volume, $V_{N}$ , of n-alkanes and polar probes upon sodium lauryl sulfate surface properties as an anionic surfactant are analyzed at diverse temperatures range from 363.15 to 433.15 K using IGC. $V_{N}$ of n-alkane values are employed to assess the London dispersive surface free energy, $γ_{S}^{L}$ by comprehensive thermodynamic models and results into the Guttmann Lewis acid-base parameters and acid-base constants. The results reveal that an excellent linear correlation coefficient value closer to 1. The current work demonstrates how to approach surface thermodynamic characteristics of anionic surfactant and suggests a new thermal model as an advanced model. Additionally, scanning electron microscopy image analysis regarding the surface morphology has been carried out using image processing techniques. Current comprehensive approach enables to analyze and apply for an effective understanding on surfactant molecules.
Inverse gas chromatography as a tool for screening materials: The relation between Lewis acid–base constants and triboelectric charge density of polymers
2022, Journal of Chromatography A
Since Saint-Flour and Papirer first introduced Gutmann's acceptor number and donor number parameters into the inverse gas chromatography (IGC) field in 1982, IGC has become an important technology for the measurement of surface Lewis acid–base properties of solid materials. However, introducing new roles of Lewis acid–base parameters, especially using them to predict material properties rather than just explain material properties, is an important aspect in developing IGC technology. In this paper, we first introduce the Schultz and Abraham methods for measurement of acid–base properties and discuss the traditional role of acid–base parameters. Then, we present a relation between the ratio of acid–base constants, K_a/K_b, and triboelectric charge density of some polymers to prove the possible new application field of IGC.
Surface thermodynamic properties of sodium carboxymethyl cellulose by inverse gas chromatography
2022, Chemical Engineering Journal Advances
This study constitutes a new development of surface thermodynamic methods to determine the London dispersive surface free energy component $γ_{s}^{d}$ , the specific free energy of adsorption and the Lewis acid-base properties of polymers by using inverse gas chromatography (IGC) at infinite dilution. The net retention volumes Vn of n-alkanes and polar solvents adsorbed on a sodium carboxymethyl cellulose (Na-CMC) polymer surface were determined at four temperatures 313.15K, 323.15K, 333.15 and -343.15K by IGC technique The London dispersive surface free energy component of Na-CMC was determined by using Dorris-Gray and Dorris-Gray-Hamieh methods, Van der Waals, Redlich-Kwong, Kiselev, geometric, cylindrical, spherical and Hamieh models. The more accurate value of $γ_{s}^{d}$ of Na-CMC was obtained by Hamieh model taking into account the thermal effect on the surface areas of molecules: $γ_{s}^{d} (T) (mJ / m^{2}) = - 0.630 T (K) + 229.01$ showing a maximal temperature T_Max = 91°C that can be considered as a new characteristic of the Na-CMC polymer. Above T_Max, there is no dispersive component of the surface energy of the polymer surface.
The specific interactions of Na-CMC particles were determined by using the various molecular models, and the vapor pressure, the boiling point, the topological index and the deformation polarization IGC methods. The obtained results clearly showed a strong Lewis basicity of Na-CMC (about seven times more basic than acidic polymer surface). It was proved that the IGC methods and models do not give similar results. The thermal model gave the most accurate result of the Lewis acid-base properties of Na-CMC surface.
Production of nanocellulose gels and films from invasive tree species
2021, International Journal of Biological Macromolecules
Wood from invasive tree species Acacia dealbata and Ailanthus altissima was used to produce high value-added nanocellulose. Firstly, bleached pulps were produced from the wood of these tree species after kraft cooking. Afterwards, the resultant pulps were pre-treated by TEMPO-mediated oxidation (Acacia dealbata) or enzymatic hydrolysis (Ailanthus altissima) followed by high-pressure homogenization. Hydrogels were obtained and characterized for their main physical and chemical properties, including rheology measurements. After freeze-drying, the surface properties of the materials were evaluated by inverse gas chromatography. Results showed that nano/micro fibrils could be obtained from the wood of these invasive species. Rheometry studies showed that Acacia-TEMPO cellulose nanofibrils form strong gels with high yield stress point and viscosities (reaching ca. 100,000 Pa·s). Additionally, the surfaces of the obtained nanocelluloses showed a dispersive component of the surface energy near 40 mJ/m² and a prevalence of the Lewis acidic character over the basic one, as typical for cellulose-based materials. Finally, films with good mechanical and optical properties could be obtained from the cellulose hydrogels. Acacia-TEMPO film (produced by filtration/hot pressing) showed a tensile strength of 79 MPa, Young's modulus of 7.9 GPa, and a transparency of 88%. The water vapor barrier, however, was modest (permeability of 4.9 × 10⁻⁶ g/(Pa·day·m)).

View all citing articles on Scopus

View full text

Analysis of interactions in multicomponent polymeric systems: The key-role of inverse gas chromatography

Abstract

Introduction

Section snippets

Thermodynamic requirements for miscibility in multicomponent polymeric systems

The solubility parameter

Interaction parameters from polymer solution theories

Work of adhesion and interfacial tension

Introduction to inverse gas chromatography (IGC)

Conclusions

Polymer

J. Non Cryst. Solids

Mater. Sci. Eng. R. Rep.

Polymer

Polymer

Polymer

J. Colloid Interface Sci.

J. Chromatogr. A

Polymer

J. Colloid Interface Sci.

Fluid Phase Equilib.

J. Colloid Interface Sci.

Powder Technol.

Polymer

Nat. Mater.

J. Adhes. Sci. Technol.

Polym. Composites

Polym. Composites

Polym. Composites

Polym. Composites

J. Macromol. Sci. A Chem.

Polym. Composites

Specific Interactions and the Miscibility of Polymer Blends

Macromolecules

J. Coat. Technol.

Adsorption on Solids

Intermolecular Forces: An Introduction to Modern Methods and Results

Intermolecular and Surface Forces

Ind. Eng. Prod. Res. Dev.

Rubber Chem. Technol.

J. Adhes. Sci. Technol.

J. Polym. Sci. B Polym. Phys.

Composite Interfaces

Polymer

Macromolecules