Estimation of the effective diffusivity of blowing agents in closed-cell low-density polyurethane foams based on thermal aging data

Andersons, J.; Modniks, Jānis; Kirpļuks, Miķelis

doi:10.1016/j.jobe.2021.103365

Cited by 9 publications

(7 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

Section: Resultsmentioning

confidence: 99%

“…The effective diffusion coefficients for cell gasses (CO 2 , PBA, and air) were determined by approximating the experimental data of thermal conductivity as a function of aging time by the theoretical prediction according to eq 5. 37 Specifically, gas diffusivities were estimated as the values minimizing the mean- square deviation of the experimental thermal aging data of the foams and the thermal conductivity predicted by eq 5. The well-established differences in gas diffusivities and the aging stages in polymer foams 23 were used to facilitate the convergence of the numerical analysis by first obtaining approximate initial estimates of diffusivities as follows.…”

Section: Effective Diffusivitiesmentioning

confidence: 99%

See 1 more Smart Citation

Effect of Crosslink Density on Thermal Aging of Bio-Based Rigid Low-Density Closed-Cell Polyurethane Foams

Kirpļuks

Godiņa

Švajdlenková

et al. 2023

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

Gradual replacement of the traditional raw materials in polyurethane (PU) synthesis by bio-based ones and introduction of environmentally friendly physical blowing agents (PBAs) motivate the analysis of thermal aging of bio-based foams in order to optimize the chemical structure of the PU matrix so that its permeability to PBA is minimized. With the aim of elucidating the effect of the PU chemical structure on thermal aging of foams, rigid low-density closed-cell PU foams were produced solely from bio-based polyols. The effective diffusivities of PBA and atmospheric gasses were evaluated based on the measured thermal conductivity aging of foams and validated by gas chromatography measurements of gas composition in foam cells. Gas permeability of the PU polymer was estimated based on effective diffusivity in foams and foam morphology and found to decrease with increasing crosslink density, apparently due to reduction in the fractional free volume in the polymers.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Effective Diffusivitiesmentioning

confidence: 99%

Effect of Crosslink Density on Thermal Aging of Bio-Based Rigid Low-Density Closed-Cell Polyurethane Foams

Kirpļuks

Godiņa

Švajdlenková

et al. 2023

ACS Appl. Polym. Mater.

Self Cite

View full text Add to dashboard Cite

show abstract

“…At present, commonly used insulation materials include polyurethane [24], glass wool [25], and expanded perlite [26]. As a kind of polymer compound, polyurethane is widely used in external insulation composite systems because of its good stability, chemical resistance, thermal insulation and resilience [27]. Ceramic has the advantages of high temperature resistance, corrosion resistance, high hardness, low creep, etc, and is widely used in many fields [28].…”

Section: Introductionmentioning

confidence: 99%

Temperature and strain characteristics of ceramic-reinforced polyurethane insulation decorative board under artificial accelerated aging conditions

Ma,

Yuan,

Xiong

et al. 2024

Mater. Res. Express

View full text Add to dashboard Cite

As a new type of thermal insulation material, ceramic-reinforced polyurethane insulation decorative board (IDB) has been applied to a certain extent, but changes in the temperature and strain between this material and the substrate wall during the aging process remain unclear. In this study, an external insulation composite system with ceramic-reinforced polyurethane IDB was subjected to 60 heat-rain cycles, and the temperature and strain at the interface between the IDB and the substrate wall were measured. The results show that the ceramic-reinforced polyurethane IDB had good thermal insulation performance and durability, while the horizontal and vertical strains exhibited serious inhomogeneity, which may be an important reason for the aging and cracking of the IDB. The characteristics of temperature and strain at the interface between the IDB and the substrate wall provide a reference for analyzing the synergistic effect and the disassembly of the two and can provide some guidance for the design and construction of external insulation composite systems.

show abstract

“…25 In this work, the gas diffusivities are predicted by determining the gas content in foams at various times. 25 In some studies about the polymer foaming processes, the measurements of the solubility and diffusivity of the gases as blowing agents in the polymer were performed prior to the foaming process. [26][27][28] The reason for this is to investigate the effect of gas solubility on its foaming properties.…”

Section: Introductionmentioning

confidence: 99%

“…24 In another study, Andersons et al, estimated the diffusivity of gases in closed-cell polyurethane foams. 25 In this work, the gas diffusivities are predicted by determining the gas content in foams at various times. 25 In some studies about the polymer foaming processes, the measurements of the solubility and diffusivity of the gases as blowing agents in the polymer were performed prior to the foaming process.…”

Section: Introductionmentioning

confidence: 99%

Effect of gelatin on the solubility and diffusivity of normal pentane in the poly (vinyl alcohol)/Gelatin blends

Azimi

2022

Journal of Thermoplastic Composite Materials

View full text Add to dashboard Cite

In this work, we investigated the effect of Gelatin on the solubility and diffusivity of normal pentane in poly (vinyl alcohol) (PVA)/Gelatin (Gel) blends. The processibility of PVA was enhanced after adding the gelatin as plasticizer to PVA which gelatin could extend the process widow of PVA with destroying the hydrogen bonding of the polymer matrix. Therefore, the PVA/Gel blends with different concentrations were prepared by simple solution-casting method. The intermolecular suitable interactions in PVA/Gel blends were confirmed using the FTIR, XRD and SEM/EDX analyzes. In the following, the effect of various factors like temperature, pressure and gelatin content on the thermodynamic parameters like specific free volume, solubility and diffusivity was investigated. It was shown that there was a relationship between the specific free volume of the blends with the solubility and diffusivity of normal pentane in blends. The specific free volume of blends was determined by applying the PVT data and the Sanchez-Lacombe (SL) equation of state, in which it was enhanced with increasing of the temperature and gelatin in blends, respectively. Also, the solubility and diffusivity of normal pentane in samples were determined by the magnetic suspension balance (MSB) system. The results presented that the solubility and diffusivity of n-pentane improved with increasing of gelatin content in blend, pressure and temperature decrement, respectively.

show abstract

Estimation of the effective diffusivity of blowing agents in closed-cell low-density polyurethane foams based on thermal aging data

Cited by 9 publications

References 25 publications

Effect of Crosslink Density on Thermal Aging of Bio-Based Rigid Low-Density Closed-Cell Polyurethane Foams

Effect of Crosslink Density on Thermal Aging of Bio-Based Rigid Low-Density Closed-Cell Polyurethane Foams

Temperature and strain characteristics of ceramic-reinforced polyurethane insulation decorative board under artificial accelerated aging conditions

Effect of gelatin on the solubility and diffusivity of normal pentane in the poly (vinyl alcohol)/Gelatin blends

Contact Info

Product

Resources

About