Anthony Andrady - Academia.edu (original) (raw)

Uploads

Papers by Anthony Andrady

Research paper thumbnail of Aerobic mineralization of paperboard materials used in packaging applications

Journal of Applied Polymer Science, Nov 14, 1999

ABSTRACT

Research paper thumbnail of Effects of solar UV and climate change on materials

Photochemical and Photobiological Sciences, Feb 1, 2011

Research paper thumbnail of Outdoor weathering of selected polymeric materials under marine exposure conditions

Polymer Degradation and Stability, 1989

Abstract Several types of thermoplastic and latex rubber materials commonly encountered in marine... more Abstract Several types of thermoplastic and latex rubber materials commonly encountered in marine plastic debris were weathered in air and while floating in sea water, under North Carolina climatic conditions. The degradation of the different samples was monitored by tensile property determination. In general, the various materials tested tended to weather at a slower rate when exposed in sea water compared to that in air. This retardation of weathering is probably a result of lack of heat build-up in samples exposed at sea.

Research paper thumbnail of A One Health perspective of the impacts of microplastics on animal, human and environmental health

Science of The Total Environment, Jul 1, 2021

Microplastics contamination is widespread in the environment leading to the exposure of both huma... more Microplastics contamination is widespread in the environment leading to the exposure of both humans and other biota. While most studies overemphasize direct toxicity of microplastics, particle concentrations, characteristics and exposure conditions being used in these assays needs to be taken into consideration. For instance, toxicity assays that use concentrations over 100,000 times higher than those expected in the environment have limited practical relevance. Thus, adverse effects on animal and human health of current environmental concentrations are identified as a knowledge gap. Conversely, this does not suggest the lack of any significant effects of microplastics on a global scale. The One Health approach provides a novel perspective focused on the intersection of different areas, namely animal, human, and environmental health. This review provides a One Health transdisciplinary approach to microplastics, addressing indirect effects beyond simple toxicological effects. Microplastics can, theoretically, change the abiotic properties of matrices (e.g., soil permeability) and interfere with essential ecosystem functions affecting ecosystem services (e.g., biogeochemical processes) that can in turn impact human health. The gathered information suggests that more research is needed to clarify direct and indirect effects of microplastics on One Health under environmentally relevant conditions, presenting detailed knowledge gaps.

Research paper thumbnail of Model networks of end‐linked polydimethylsiloxane chains. VII. Networks designed to demonstrate non‐Gaussian effects related to limited chain extensibility

Journal of Chemical Physics, Feb 15, 1980

End-linking polymer chains by means of a multifunctional cross-linking agent provides an ideal wa... more End-linking polymer chains by means of a multifunctional cross-linking agent provides an ideal way for obtaining elastomeric networks of any desired distribution of chain lengths. In the present investigation, this technique was employed to give polydimethylsiloxane networks consisting of various proportions of relatively long and very short network chains. The stress–strain isotherms of these networks generally showed an anomalous increase in the modulus at high elongation, and the increase persisted at high temperatures and high degrees of swelling. This non-Gaussian effect was quantitatively correlated with the limited extensibility of the network chains; specifcally, the increase in modulus was found to begin at approximately 60%–70% of the maximum extensibility of the network chains, and network rupture at 80%–90%. The elongation at which the increase becomes evident increases with decrease in the proportion of the very short chains, thus verifying the nonaffine nature of the deformation at high elongation. In addition, the elasticity constants characterizing the Gaussian regions of the isotherms, and the values of the degree of equilibrium swelling were used to evaluate the most recent molecular theories of rubberlike elasticity, particularly with regard to the structure factor relating the modulus of an elastomer to the average length or molecular weight of the network chains.

Research paper thumbnail of Science and Technology of Polymer Nanofibers

Research paper thumbnail of Mechanical and gas transport properties of poly-ε-caprolactone model networks

Journal of Applied Polymer Science, Nov 1, 1984

Research paper thumbnail of Light stabilization of polymers using opaque pigments

Journal of Applied Polymer Science, Mar 1, 1987

ABSTRACT

Research paper thumbnail of Estimation of Rates of Drug Diffusion in Polymers

Acs Symposium Series, Sep 4, 1987

Research paper thumbnail of Glass transition in poly(propylene glycol) networks

Journal of polymer science, Dec 1, 1983

Research paper thumbnail of Chemical sensing using electrospun polymer/carbon nanotube composite nanofibers with printed-on electrodes

Sensors and Actuators B-chemical, Sep 1, 2013

Abstract An integrated sensor system was developed using mats formed of electrospun polymer/singl... more Abstract An integrated sensor system was developed using mats formed of electrospun polymer/single-walled carbon nanotube composite nanofibers combined with inter-digitated electrodes directly printed on the surface to detect volatile organic compounds. When the polymer in the fibers swells due to vapor adsorption, the carbon nanotubes separate from each other and increase electrical resistance of the material. The conductivity change of the composite-sensing material was monitored with a multi-meter when exposed to volatile organic compounds. The response to different vapors showed a linear relationship between resistance change and vapor concentration. We obtained both sensitivity and selectivity data on the sensor with several different vapor analytes – methanol is used as an example in this paper.

Research paper thumbnail of Environmental effects of ozone depletion and its interactions with climate change: progress report, 2009

Photochemical and Photobiological Sciences, Mar 1, 2010

Research paper thumbnail of Interactive effects of solar UV radiation and climate change on material damage

Photochemical and Photobiological Sciences, Mar 1, 2019

Research paper thumbnail of Research and development of two marine-degradable biopolymers. Rept. for 1 Oct 89-30 Sep 90

Research paper thumbnail of Biodegradability of Polymers

Springer eBooks, 2007

Page 1. CHAPTER 56 Biodegradability of Polymers Anthony L. Andrady Engineering & Tech... more Page 1. CHAPTER 56 Biodegradability of Polymers Anthony L. Andrady Engineering & Technology Dirsian, RTI International, Research Triangle Park, NC 27709 56.1 Introduction . . . . . ...

Research paper thumbnail of Effects of dangling chains on some dynamic mechanical properties of model poly(dimethylsiloxane) networks

Polymer Bulletin, Mar 1, 1992

Research paper thumbnail of Transport of hydrogen and carbon monoxide in highly crosslinked poly(propylene glycol) networks

Journal of polymer science, Feb 1, 1984

Research paper thumbnail of Weathering and fragmentation of plastic debris in the ocean environment

Marine Pollution Bulletin, Jul 1, 2022

Research paper thumbnail of Thermogravimetric determination of starch content in starch–polyethylene blend films

Journal of Applied Polymer Science, Aug 15, 1992

ABSTRACT

Research paper thumbnail of <sup>129</sup>Xe NMR Investigation of the Free Volume in Dendritic and Cross-Linked Polymers

Macromolecules, Feb 26, 1999

129Xe NMR spectroscopy was used to study the free-volume changes associated with cross-linking of... more 129Xe NMR spectroscopy was used to study the free-volume changes associated with cross-linking of linear polymers and extensive chain branching in dendritic tree molecules. Qualitative changes in the free volume in model networks of poly(oxypropylene) and in starburst dendrimers of poly(amidoamine) were studied as a function of the cross-link density and the generation, respectively. Consistent with the present understanding of these end-linked networks, the change in chemical shift of the xenon was found to correlate well with the reciprocal of the average molecular weight between cross-links of the end-linked networks. With dendrimers, the chemical shift of xenon varied linearly with the generation number. A modified form of the chain-end free volume theory applicable to dendritic molecules was used to interpret the data.

Research paper thumbnail of Aerobic mineralization of paperboard materials used in packaging applications

Journal of Applied Polymer Science, Nov 14, 1999

ABSTRACT

Research paper thumbnail of Effects of solar UV and climate change on materials

Photochemical and Photobiological Sciences, Feb 1, 2011

Research paper thumbnail of Outdoor weathering of selected polymeric materials under marine exposure conditions

Polymer Degradation and Stability, 1989

Abstract Several types of thermoplastic and latex rubber materials commonly encountered in marine... more Abstract Several types of thermoplastic and latex rubber materials commonly encountered in marine plastic debris were weathered in air and while floating in sea water, under North Carolina climatic conditions. The degradation of the different samples was monitored by tensile property determination. In general, the various materials tested tended to weather at a slower rate when exposed in sea water compared to that in air. This retardation of weathering is probably a result of lack of heat build-up in samples exposed at sea.

Research paper thumbnail of A One Health perspective of the impacts of microplastics on animal, human and environmental health

Science of The Total Environment, Jul 1, 2021

Microplastics contamination is widespread in the environment leading to the exposure of both huma... more Microplastics contamination is widespread in the environment leading to the exposure of both humans and other biota. While most studies overemphasize direct toxicity of microplastics, particle concentrations, characteristics and exposure conditions being used in these assays needs to be taken into consideration. For instance, toxicity assays that use concentrations over 100,000 times higher than those expected in the environment have limited practical relevance. Thus, adverse effects on animal and human health of current environmental concentrations are identified as a knowledge gap. Conversely, this does not suggest the lack of any significant effects of microplastics on a global scale. The One Health approach provides a novel perspective focused on the intersection of different areas, namely animal, human, and environmental health. This review provides a One Health transdisciplinary approach to microplastics, addressing indirect effects beyond simple toxicological effects. Microplastics can, theoretically, change the abiotic properties of matrices (e.g., soil permeability) and interfere with essential ecosystem functions affecting ecosystem services (e.g., biogeochemical processes) that can in turn impact human health. The gathered information suggests that more research is needed to clarify direct and indirect effects of microplastics on One Health under environmentally relevant conditions, presenting detailed knowledge gaps.

Research paper thumbnail of Model networks of end‐linked polydimethylsiloxane chains. VII. Networks designed to demonstrate non‐Gaussian effects related to limited chain extensibility

Journal of Chemical Physics, Feb 15, 1980

End-linking polymer chains by means of a multifunctional cross-linking agent provides an ideal wa... more End-linking polymer chains by means of a multifunctional cross-linking agent provides an ideal way for obtaining elastomeric networks of any desired distribution of chain lengths. In the present investigation, this technique was employed to give polydimethylsiloxane networks consisting of various proportions of relatively long and very short network chains. The stress–strain isotherms of these networks generally showed an anomalous increase in the modulus at high elongation, and the increase persisted at high temperatures and high degrees of swelling. This non-Gaussian effect was quantitatively correlated with the limited extensibility of the network chains; specifcally, the increase in modulus was found to begin at approximately 60%–70% of the maximum extensibility of the network chains, and network rupture at 80%–90%. The elongation at which the increase becomes evident increases with decrease in the proportion of the very short chains, thus verifying the nonaffine nature of the deformation at high elongation. In addition, the elasticity constants characterizing the Gaussian regions of the isotherms, and the values of the degree of equilibrium swelling were used to evaluate the most recent molecular theories of rubberlike elasticity, particularly with regard to the structure factor relating the modulus of an elastomer to the average length or molecular weight of the network chains.

Research paper thumbnail of Science and Technology of Polymer Nanofibers

Research paper thumbnail of Mechanical and gas transport properties of poly-ε-caprolactone model networks

Journal of Applied Polymer Science, Nov 1, 1984

Research paper thumbnail of Light stabilization of polymers using opaque pigments

Journal of Applied Polymer Science, Mar 1, 1987

ABSTRACT

Research paper thumbnail of Estimation of Rates of Drug Diffusion in Polymers

Acs Symposium Series, Sep 4, 1987

Research paper thumbnail of Glass transition in poly(propylene glycol) networks

Journal of polymer science, Dec 1, 1983

Research paper thumbnail of Chemical sensing using electrospun polymer/carbon nanotube composite nanofibers with printed-on electrodes

Sensors and Actuators B-chemical, Sep 1, 2013

Abstract An integrated sensor system was developed using mats formed of electrospun polymer/singl... more Abstract An integrated sensor system was developed using mats formed of electrospun polymer/single-walled carbon nanotube composite nanofibers combined with inter-digitated electrodes directly printed on the surface to detect volatile organic compounds. When the polymer in the fibers swells due to vapor adsorption, the carbon nanotubes separate from each other and increase electrical resistance of the material. The conductivity change of the composite-sensing material was monitored with a multi-meter when exposed to volatile organic compounds. The response to different vapors showed a linear relationship between resistance change and vapor concentration. We obtained both sensitivity and selectivity data on the sensor with several different vapor analytes – methanol is used as an example in this paper.

Research paper thumbnail of Environmental effects of ozone depletion and its interactions with climate change: progress report, 2009

Photochemical and Photobiological Sciences, Mar 1, 2010

Research paper thumbnail of Interactive effects of solar UV radiation and climate change on material damage

Photochemical and Photobiological Sciences, Mar 1, 2019

Research paper thumbnail of Research and development of two marine-degradable biopolymers. Rept. for 1 Oct 89-30 Sep 90

Research paper thumbnail of Biodegradability of Polymers

Springer eBooks, 2007

Page 1. CHAPTER 56 Biodegradability of Polymers Anthony L. Andrady Engineering &amp;amp; Tech... more Page 1. CHAPTER 56 Biodegradability of Polymers Anthony L. Andrady Engineering &amp;amp; Technology Dirsian, RTI International, Research Triangle Park, NC 27709 56.1 Introduction . . . . . ...

Research paper thumbnail of Effects of dangling chains on some dynamic mechanical properties of model poly(dimethylsiloxane) networks

Polymer Bulletin, Mar 1, 1992

Research paper thumbnail of Transport of hydrogen and carbon monoxide in highly crosslinked poly(propylene glycol) networks

Journal of polymer science, Feb 1, 1984

Research paper thumbnail of Weathering and fragmentation of plastic debris in the ocean environment

Marine Pollution Bulletin, Jul 1, 2022

Research paper thumbnail of Thermogravimetric determination of starch content in starch–polyethylene blend films

Journal of Applied Polymer Science, Aug 15, 1992

ABSTRACT

Research paper thumbnail of <sup>129</sup>Xe NMR Investigation of the Free Volume in Dendritic and Cross-Linked Polymers

Macromolecules, Feb 26, 1999

129Xe NMR spectroscopy was used to study the free-volume changes associated with cross-linking of... more 129Xe NMR spectroscopy was used to study the free-volume changes associated with cross-linking of linear polymers and extensive chain branching in dendritic tree molecules. Qualitative changes in the free volume in model networks of poly(oxypropylene) and in starburst dendrimers of poly(amidoamine) were studied as a function of the cross-link density and the generation, respectively. Consistent with the present understanding of these end-linked networks, the change in chemical shift of the xenon was found to correlate well with the reciprocal of the average molecular weight between cross-links of the end-linked networks. With dendrimers, the chemical shift of xenon varied linearly with the generation number. A modified form of the chain-end free volume theory applicable to dendritic molecules was used to interpret the data.