Journal Browser

► Journal Browser

Special Issue "Polymer Degradation in Various Environment Conditions—Experimental Method and Numerical Modeling"

Share This Special Issue

Special Issue Editor

E-Mail Website
Guest Editor

Center for Mechanical and Aerospace Science and Technologies (C-MAST-UBI), Universidade da Beira Interior, R. Marquês D’Ávila e Bolama, 6201-001 Covilhã, Portugal
Interests: composite materials; biodegradation; viscoplastic behavior; biomechanical design; solid mechanics; finite element modeling
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Biodegradable polymers find applications in many market segments. Among its main advantages is its ability to meet mechanical requirements within a certain time range, after which it degrades and is naturally absorbed. This ability can thus be used in the controlled release of substances such as fertilizers, perfumes, drugs, etc. On the other hand, short-use products can be easily disposable, saving significantly in terms of waste removal. Typical examples of applications of these materials are fishing nets or agricultural devices used during one season. In the field of medical devices used in regenerative medicine, these materials are used in combination with cells to produce temporary implants that replace the mechanical functions of the extracellular matrix, while the biological tissue gradually regenerates and replaces the implant that degrades and is naturally assimilated by the human body. This way, implant removal surgeries are avoided. In many situations, these types of solutions can replace transplants, autografts or xenografts. However, the design of these temporary devices still presents great challenges, namely, in the verification of the main requirement: the lifetime of the device, associated with the progressive loss of mechanical properties, until its complete erosion and assimilation. Thus, this Special Issue will be devoted to present new approaches and methodologies used to simulate the polymeric device’s mechanical behavior during its hydrolytic degradation.

Dr. André Ferreira Costa Vieira
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Polymers is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

biodegradable polymers
hydrolysis
degradation
mechanical behavior
erosion
mass loss
simulation

Published Papers (2 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Research

Open AccessArticle

Numerical Approach to Simulate the Mechanical Behavior of Biodegradable Polymers during Erosion

André F. C. Vieira

Enio H. P. Da Silva

and

Marcelo L. Ribeiro

Polymers 2023, 15(9), 1979; https://doi.org/10.3390/polym15091979 - 22 Apr 2023

Viewed by 717

Abstract

Biodegradable polymers find applications in many market segments. The ability to meet mechanical requirements within a certain time range, after which it degrades and is naturally absorbed, can be used to produce short-term use products that can be easily disposable with less environmental impact. In the segment of medical devices used in regenerative medicine, these materials are used to produce temporary implants that are naturally assimilated by the human body, avoiding a removal surgery. However, the design of these temporary devices still presents great challenges, namely in the verification of the main requirement: the lifetime of the device, associated with the progressive loss of mechanical properties, until its complete erosion and assimilation. Thus, in this study, a numerical approach is proposed to simulate the polymeric device’s mechanical behavior during its hydrolytic degradation by combining the hydrolysis kinetics, that depends on mechanical factors and promotes a decrease of molecular weight and consequent decrease of mechanical performance, and erosion, when molecular weight reaches a threshold value and the polymer becomes soluble and diffuses outward, resulting in mass loss and decreasing cross-sectional area, which also contributes to the mechanical performance reduction of the device. A phenomenological approach, using the combination of continuum-based hydrolytic damage for the evolution of mechanical properties that depends on the stress field and further removal of the degraded element (to simulate mass loss) was used. Both elastoplastic and hyperelastic constitutive models were applied on this study, where the material model parameters locally depend on the molecular weight. Full article

(This article belongs to the Special Issue Polymer Degradation in Various Environment Conditions—Experimental Method and Numerical Modeling)

► Show Figures

Figure 1

Open AccessArticle

Accelerated Aging on the Compression Properties of a Green Polyurethane Foam: Experimental and Numerical Analysis

and

Polymers 2023, 15(7), 1784; https://doi.org/10.3390/polym15071784 - 03 Apr 2023

Cited by 1 | Viewed by 1437

Abstract

The aim of this work is to evaluate the changes in compression properties of a bio-based polyurethane foam after exposure to 90 °C for different periods of time, and to propose a method to extrapolate these results and use a numerical approach to predict the compression behaviour after degradation for untested conditions at different degradation times and temperatures. Bio-based polymers are an important sustainable alternative to oil-based materials. This is explained by the foaming process and the density along the material as it was possible to see in a digital image correlation analysis. After 60 days, stiffness was approximately decreased by half in both directions. The decrease in yield stress due to thermo-oxidative degradation had a minor effect in the foaming directions, changing from 352 kPa to 220 kPa after 60 days, and the transverse property was harshly impacted changing from 530 kPa to 265 kPa. The energy absorption efficiency was slightly affected by degradation. The simulation of the compression stress-strain curves were in accordance to the experimental data and made it possible to predict the changes in mechanical properties for intermediate periods of degradation time. The plateau stress for the unaged foam transverse to the foaming direction presented experimental and numerical values of 450 kPa and 470 kPa, respectively. In addition, the plateau stresses in specimens degraded for 40 days present very similar experimental and numerical results in the same direction, at 310 kPa and 300 kPa, respectively. Therefore, this paper presents important information regarding the life-span and degradation of a green PUF. It provides insights into how compression properties vary along degradation time as function of material operation temperature, according to the Arrhenius degradation equation. Full article

(This article belongs to the Special Issue Polymer Degradation in Various Environment Conditions—Experimental Method and Numerical Modeling)

► Show Figures

Journal Menu

Journal Browser

Special Issue "Polymer Degradation in Various Environment Conditions—Experimental Method and Numerical Modeling"

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (2 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI