Controlling Bicontinuous Structures through a Solvent Segregation-Driven Gel.

The past decade has seen increased research interest in studying bicontinuous structures formed via colloidal self-assembly due to their many useful applications. A new type of colloidal gel, solvent segregation-driven gel (SeedGel), has been recently demonstrated as an effective approach to arrest bicontinuous structures with unique and intriguing properties, such as thermoreversibility, structural reproducibility, and sensitive temperature response. Here, using a model system with silica particles in the 2,6-lutidine/water binary solvent, we investigate the factors controlling the domain size of a SeedGel system by varying the particle concentration, solvent ratio, and quenching protocol. A phase diagram is identified to produce SeedGels for this model system. Our results indicate that by adjusting the sample composition, it is possible to realize bicontinuous domains with well-controlled repeating distances (periodicities). In addition, the effect of quenching rate on the domain size is systematically investigated, showing that it is a very sensitive parameter to control domain sizes. By further heating SeedGel up into the spinodal region, the structure evolution under high temperatures is also investigated and discussed. These results provide important insights into how to control bicontinuous structures in SeedGel systems.

Micro and macroscopic mechanical behaviors of high-density polyethylene under UV irradiation and temperature.

The macroscopic mechanical behavior of high-density polyethylene (HDPE) during photodegradation is characterized by decreases of tensile elongation-at-failure. An apparent linear relation between the elongation-at-failure and the molar mass indicates that the decrease of the elongation of HDPE over time is highly dependent on the decrease of the average molar mass. Possible preferential scission of the high molar mass chains was observed for HDPE exposed to ultraviolet (UV) irradiance higher than 40% (61 W/m2) of the full intensity at 50 °C. Tensile modulus of HDPE exposed at 50 °C increased with the exposure time until reaching the complete loss of ductility except the 5% UV. For 40% UV/30 °C as well as for 5% UV/50 °C, the young modulus trend cannot be evaluated with performed (small) duration. Nanomechanical test results suggest that the increased tensile modulus is due to stiffening of the entire cross-section. Furthermore, HDPE showing the complete loss of ductility exhibited significantly higher modulus in the surface regions than the core regions particularly for the UV intensity higher than 40% (61 W/m2), which increased crack sensitivity to cause embrittlement of the entire specimens.

Graphene/polymer nanocomposite degradation by ultraviolet light: The effects of graphene nanofillers and their potential for release.

The ultraviolet (UV)-induced degradation of graphene/polymer nanocomposites was investigated in this study. Specifically, the effect of few-layer graphene nanofillers on the degradation of a thermoplastic polyurethane (TPU) and the release potential of graphene from the degraded nanocomposite surfaces were assessed. Graphene/TPU (G/TPU) nanocomposites and neat TPU were UV-exposed under both dry and humid conditions in the NIST SPHERE, a precisely controlled, high intensity UV-weathering device. Neat TPU and G/TPU were characterized over the time course of UV exposure using color measurements and infrared spectroscopy, for appearance and chemical changes, respectively. Changes in thickness and surface morphology were obtained with scanning electron microscopy. A new fluorescence quenching measurement approach was developed to identify graphene sheets at the nanocomposite surface, which was supported by contact angle measurements. The potential for graphene release from the nanocomposite surface was evaluated using a tape-lift method followed by microscopy of any particles present on the tape. The findings suggest that graphene improves the service life of TPU with respect to UV exposure, but that graphene becomes exposed at the nanocomposite surface over time, which may potentially lead to its release when exposed to small mechanical forces or upon contact with other materials.

Accelerated weathering parameters for some aromatic engineering thermoplastics.

Samples of polycarbonate (PC), poly(butylene terephthalate) (PBT), a PC/PBT blend, and poly(styrene-co-acrylonitrile) (SAN), all containing 3% TiO2 (by mass), were exposed in the NIST (National Institutes of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) to determine the effects of UV intensity (irradiance), temperature, relative humidity (RH), and UV wavelength on yellowing and gloss loss. There was no effect of irradiance, such that the samples obeyed reciprocity and doubling the irradiance doubled the rate of degradation. The activation energy for yellowing was determined to be ≈ 20 kJ/mol for PC, PC/PBT, and SAN and ≈ 16 kJ/mol for PBT. The activation energy for gloss loss was determined to be 9-16 kJ/mol. Thus, a 10 °C increase in temperature results in a 20%-30% increase in degradation rate. There was no consistent effect of RH on PC or PC/PBT yellowing or gloss loss. SAN degraded rapidly under dry conditions but showed little effect for RH > 10%. PBT lost gloss more slowly under dry conditions but displayed no RH effect with yellowing. Shorter wavelength UV had a greater effect on PC/PBT compared to PC or PBT.

Accelerated weathering parameters for some aromatic engineering thermoplastics. Part 2: Polycarbonate copolymers, polyarylate and ABS.

Understanding the responses of materials to environmental variables is essential for performing meaningful accelerated weathering and service life prediction. Samples of polycarbonate-b-resorcinol polyarylate copolymer (RPA), poly(acrylonitrile-co-butadiene-co-styrene) (ABS), and two polycarbonate copolymers with silicone or aliphatic diacids were exposed in the NIST (National Institute of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) to determine the effects of ultraviolet intensity (UV irradiance), temperature, relative humidity (RH), and UV wavelength on yellowing and gloss loss and were compared to other aromatic polymers. All showed proportional response to irradiance (i.e., reciprocity) except ABS, which deviated notably at elevated temperatures. The activation energy for ABS yellowing was higher than other aromatic polymers (31 kJ mol-1 ± 2 kJ mol-1) while RPA had a slightly negative activation energy (-5 kJ mol-1 ± 3 kJ mol-1), reflecting differences in their photodegradation mechanisms. These two polymers also exhibited faster degradation when the RH was ≤ 10 % compared to ≥ 50 % RH. Wavelength effects varied among the polymers. The results indicate that predictive accelerated weathering should be performed with UV sources that accurately reproduce sunlight, at temperatures as close as possible to use conditions, and with RH > 10 %.

Detection and Quantification of Graphene-Family Nanomaterials in the Environment.

An increase in production of commercial products containing graphene-family nanomaterials (GFNs) has led to concern over their release into the environment. The fate and potential ecotoxicological effects of GFNs in the environment are currently unclear, partially due to the limited analytical methods for GFN measurements. In this review, the unique properties of GFNs that are useful for their detection and quantification are discussed. The capacity of several classes of techniques to identify and/or quantify GFNs in different environmental matrices (water, soil, sediment, and organisms), after environmental transformations, and after release from a polymer matrix of a product is evaluated. Extraction and strategies to combine methods for more accurate discrimination of GFNs from environmental interferences as well as from other carbonaceous nanomaterials are recommended. Overall, a comprehensive review of the techniques available to detect and quantify GFNs are systematically presented to inform the state of the science, guide researchers in their selection of the best technique for the system under investigation, and enable further development of GFN metrology in environmental matrices. Two case studies are described to provide practical examples of choosing which techniques to utilize for detection or quantification of GFNs in specific scenarios. Because the available quantitative techniques are somewhat limited, more research is required to distinguish GFNs from other carbonaceous materials and improve the accuracy and detection limits of GFNs at more environmentally relevant concentrations.

Impact of UV irradiation on multiwall carbon nanotubes in nanocomposites: formation of entangled surface layer and mechanisms of release resistance.

Multiwall carbon nanotubes (MWCNTs) are nanofillers used in consumer and structural polymeric products to enhance a variety of properties. Under weathering, the polymer matrix will degrade and the nanofillers may be released from the products potentially impacting ecological or human health. In this study, we investigated the degradation of a 0.72 % (by mass) MWCNT/amine-cured epoxy nanocomposite irradiated with high intensity ultraviolet (UV) light at various doses, the effects of UV exposure on the surface accumulation and potential release of MWCNTs, and possible mechanisms for the release resistance of the MWCNT surface layer formed on nanocomposites by UV irradiation. Irradiated samples were characterized for chemical degradation, mass loss, surface morphological changes, and MWCNT release using a variety of analytical techniques. Under 295 nm to 400 nm UV radiation up to a dose of 4865 MJ/m2, the nanocomposite matrix underwent photodegradation, resulting in formation of a dense, entangled MWCNT network structure on the surface. However, no MWCNT release was detected, even at very high UV doses, suggesting that the MWCNT surface layer formed from UV irradiation of polymer nanocomposites resist release. Four possible release resistance mechanisms of the UV-induced MWCNT surface layer are presented and discussed.

Changes in the Chemical Composition of Polyethylene Terephthalate Under UV Radiation in Various Environmental Conditions.

Polyethylene terephthalate has been widely used in the packaging industry. Degraded PET micro-nano plastics could pose public health concerns following release into various environments. This study focuses on PET degradation under ultraviolet radiation using the NIST SPHERE facility at the National Institute of Standards and Technology in saturated humidity (i.e., ≥ 95 % relative humidity) and dry conditions (i.e., ≤ 5 % relative humidity) with varying temperatures (30 °C, 40 °C, and 50 °C) for up 20 days. ATR-FTIR was used to characterize the chemical composition change of degraded PET as a function of UV exposure time. The results showed that the cleavage of the ester bond at peak 1713 cm-1 and the formation of the carboxylic acid at peak 1685 cm-1 are significantly influenced by UV radiation. Furthermore, the formation of carboxylic acid was considerably higher at saturated humidity and 50 °C conditions compared to dry conditions. The ester bond cleavage was also more pronounced in saturated humidity conditions. The novelty of this study is to provide insights into the chemical degradation of PET under environmental conditions, including UV radiation, humidity, and temperature. The results can be used to develop strategies to reduce the environmental impact of plastic pollution.

Assessing children's potential exposures to harmful metals in tire crumb rubber by accelerated photodegradation weathering.

Whether a tire crumb rubber (TCR) playground would expose children to potentially harmful chemicals such as heavy metals is an open question. The released metals available for pickup on the surface of TCR tiles was studied by accelerated 2-year aging of the TCRs in the NIST-SPHERE (National Institute of Standards and Technology Simulated Photodegradation via High Energy Radiant Exposure). The dermal contact was mimicked by a method of composite surface wiping from US Environmental Protection Agency throughout the weathering process. The surface release of ten most concerned harmful metals (Be, Cr, Cu, As, Se, Cd, Sb, Ba, Tl, Pb) was monitored through the course of aging. The cumulative release of Cu, As, Tl, and Sb reached potentially harmful levels at various times within 3 years, although only Cr was found at a harmful level on the surface of the tiles. Taking the cleansing effect of precipitation or periodic cleansing with rain into account, TCR playgrounds may still be safe for use.

Quantitative evaluation of released nanomaterials from carbon nanotube epoxy nanocomposites during environmental exposure and mechanical treatment.

Carbon nanotubes (CNTs) are promising nanomaterials exhibiting high thermal and electrical conductivities, significant stiffness, and high tensile strength. As a result, CNTs have been utilized as additives to enhance properties of various polymeric materials in a broad range of fields. In this study, we investigated the release of CNTs from CNT epoxy nanocomposites exposed to environmental weathering and mechanical stresses. The presence and amount of CNTs released from degraded polymer nanocomposites is important because CNTs can impact physiological systems in humans and environmental organisms. The weathering experiments in this study included nanocomposite exposure to both UV and a water spray, to simulate sunlight and rain exposure, whereas mechanical stresses were induced by shaking and ultrasonication. CNT release from epoxy nanocomposites was quantified by a 14C-labeling method that enabled measurement of the CNT release rates after different weathering and mechanical treatments. In this study, a sample oxidizer was used prior to liquid scintillation counting, because it was shown to reduce interferences from the presence of polymeric materials and achieve a high recovery (95%). Polymer nanocomposite degradation was confirmed by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), and light microscopy. A continuous release of 14C-labeled nanomaterials was observed after each UV and simulated rain exposure period, with 0.23% (mass/mass) of the total embedded mass of CNTs being released from the CNT nanocomposite during the full weathering process, suggesting that the water spray induced sufficient mechanical stress to eliminate the protective effect of the surface agglomerated CNT network. Importantly, additional mechanical stresses imposed on the weathered nanocomposites by shaking and ultrasonication resulted in further release of approximately 0.27% (mass /mass).

Tunable thermo-reversible bicontinuous nanoparticle gel driven by the binary solvent segregation.

Bicontinuous porous structures through colloidal assembly realized by non-equilibrium process is crucial to various applications, including water treatment, catalysis and energy storage. However, as non-equilibrium structures are process-dependent, it is very challenging to simultaneously achieve reversibility, reproducibility, scalability, and tunability over material structures and properties. Here, a novel solvent segregation driven gel (SeedGel) is proposed and demonstrated to arrest bicontinuous structures with excellent thermal structural reversibility and reproducibility, tunable domain size, adjustable gel transition temperature, and amazing optical properties. It is achieved by trapping nanoparticles into one of the solvent domains upon the phase separation of the binary solvent. Due to the universality of the solvent driven particle phase separation, SeedGel is thus potentially a generic method for a wide range of colloidal systems.

Selection of an Optimal Abrasion Wheel Type for Nano-Coating Wear Studies under Wet or Dry Abrasion Conditions.

Nanocoatings have numerous potential applications in the indoor environment, such as flooring finishes with increased scratch- and wear-resistance. However, given concerns about the potential environmental and human health effects of nanomaterials, it is necessary to develop standardized methods to quantify nanomaterial release during use of these products. One key choice for mechanical wear studies is the abrasion wheel. Potential limitations of different wheels include the release of fragments from the wheel during abrasion, wearing of the wheel from the abrasion process, or not releasing a sufficient number of particles for accurate quantitative analysis. In this study, we evaluated five different wheels, including a typically used silicon oxide-based commercial wheel and four wheels fabricated at the National Institute of Standards and Technology (NIST), for their application in nanocoating abrasion studies. A rapid, nondestructive laser scanning confocal microscopy method was developed and used to identify released particles on the abraded surfaces. NIST fabricated a high performing wheel: a noncorrosive, stainless-steel abrasion wheel containing a deep cross-patch. This wheel worked well under both wet and dry conditions, did not corrode in aqueous media, did not release particles from itself, and yielded higher numbers of released particles. These results can be used to help develop a standardized protocol for surface release of particles from nanoenabled products using a commercial rotary Taber abraser.

The Impacts of Moisture and Ultraviolet Light on the Degradation of Graphene Oxide/Polymer Nanocomposites.

The extent to which hydrophilic GO nanofillers regulate polymer degradation during exposure to a combination of ultraviolet (UV) radiation and moisture is presently unknown. Accordingly, this study systematically evaluated the effect of GO on polymer degradability under both humid UV and dry UV conditions. Both GO accumulation at the polymer nanocomposite (PNC) surface and GO release following degradation were also investigated. Different mass loadings of GO were incorporated into waterborne polyurethane (WBPU), a commonly used exterior coating, and the resulting GO/WBPU nanocomposites were exposed to precisely controlled accelerated weathering conditions using the NIST Simulated Photodegradation via High Energy Radiant Exposure (SPHERE) device. Thickness loss and infrared spectroscopy measurements indicated GO slightly improved the durability of WBPU under dry UV conditions but not under humid UV conditions. Raman spectroscopy, scanning electron microscopy, and atomic force microscopy modulus measurements indicated that GO accumulation occurred at and near the PNC surface under both conditions but to a more rapid extent under humid UV conditions. Minimal GO release occurred under dry UV conditions as measured with Raman spectroscopy of aqueous run-off from a simulated rain spray applied to degraded PNCs. In contrast, PNC surface transformations under humid UV conditions suggested that GO release occurred.

Evaluating performance, degradation, and release behavior of a nanoform pigmented coating after natural and accelerated weathering.

Pigments with nanoscale dimensions are added to exterior coatings to achieve desirable color and gloss properties. The present study compared the performance, degradation, and release behavior of an acrylic coating that was pigmented by a nanoform of Cu-phthalocyanine after both natural (i.e., outdoor) and accelerated weathering. Samples were weathered outdoors in three geographically distinct locations across the United States (Arizona, Colorado, Maryland) continuously for 15 months. Identically prepared samples were also artificially weathered under accelerated conditions (increased ultraviolet (UV) light intensity and elevated temperatures) for three months, in one-month increments. After exposure, both sets of samples were characterized with color, gloss, and infrared spectroscopy measurements, and selectively with surface roughness measurements. Results indicated that UV-driven coating oxidation was the principal degradation pathway for both natural and accelerated weathering samples, with accelerated weathering leading to an increased rate of oxidation without altering the fundamental degradation pathway. The inclusion of the nanoform pigment reduced the rate of coating oxidation, via UV absorption by the pigment, leading to improved coating integrity compared to non-pigmented samples. Release measurements collected during natural weathering studies indicated there was never a period of weathering, in any location, that led to copper material release above background copper measurements. Lab-based release experiments performed on samples weathered naturally and under accelerated conditions found that the release of degraded coating material after each type of exposure was diminished by the inclusion of the nanoform pigment. Release measurements also indicated that the nanoform pigment remained embedded within the coating and did not release after weathering.

Long-term wear effects on nanosilver release from commercially available food contact materials.

Potential consumer exposure to nanoparticles (NPs) from nanoenabled food contact materials (FCMs) has been a driving force for migration studies of NPs from FCMs. Although NP migration from fresh, unused FCMs was not previously observed, conditions that result in significant changes to the surface of FCMs have not been investigated for NP migration into food. Therefore, a quantitative assessment of nanoparticle release from commercially available nanosilver-enabled FCMs was performed using an abrasion protocol to simulate cleaning, cutting, scraping and other stressful use conditions. Laser scanning confocal microscopy (LSCM) analysis showed a general increase in root mean square (RMS) roughness after FCM abrasion, and particle count (for particle sizes from 80 nm to 960 nm) at the surface was 4 orders of magnitude higher for the abraded FCMs. Migration was evaluated using both water and 3% (v/v, volume fraction) acetic acid as food simulants. Low concentrations of total Ag were detected in water simulants with a small portion (<10 ng dm-2) in the form of silver nanoparticles (AgNPs). Median particle diameter ranged from 39 nm to 50 nm with particle number concentrations on the order of 106 particles dm- 2. Total Ag migration into 3% (v/v) acetic acid was significantly higher than in water; however, 3% (v/v) acetic acid was not suitable for evaluation of NP release due to dissolution of AgNPs to Ag+ under acidic solution chemistries.

Long-term wear effects on nanosilver release from commercially available food contact materials.

Potential consumer exposure to nanoparticles (NPs) from nanoenabled food contact materials (FCMs) has been a driving force for migration studies of NPs from FCMs. Although NP migration from fresh, unused FCMs was not previously observed, conditions that result in significant changes to the surface of FCMs have not been investigated for NP migration into food. Therefore, a quantitative assessment of nanoparticle release from commercially available nanosilver-enabled FCMs was performed using an abrasion protocol to simulate cleaning, cutting, scraping and other stressful use conditions. Laser scanning confocal microscopy (LSCM) analysis showed a general increase in root mean square (RMS) roughness after FCM abrasion, and particle count (for particle sizes from 80 nm to 960 nm) at the surface was 4 orders of magnitude higher for the abraded FCMs. Migration was evaluated using both water and 3% (v/v, volume fraction) acetic acid as food simulants. Low concentrations of total Ag were detected in water simulants with a small portion (<10 ng dm-2) in the form of silver nanoparticles (AgNPs). Median particle diameter ranged from 39 nm to 50 nm with particle number concentrations on the order of 106 particles dm- 2. Total Ag migration into 3% (v/v) acetic acid was significantly higher than in water; however, 3% (v/v) acetic acid was not suitable for evaluation of NP release due to dissolution of AgNPs to Ag+ under acidic solution chemistries.

Effects of consumer use practices on nanosilver release from commercially available food contact materials.

Migration evaluation involving nano-enabled food contact materials (FCMs) mostly focuses on potential nanoparticle release from new unused products. This may not represent consumer use practices encountered by the FCMs in their lifecycle. In order to determine if product use impacts the release of nanoparticles or other FCM components, it is necessary to perform migration evaluations under typical consumer use scenarios. A quantitative assessment of nanoparticle release from a commercially available nanosilver-enabled cutting board was performed under five conditions intended to simulate consumer use. Knife motion, washing and scratching scenarios were simulated by linear abrasion using knife blades, scrubbing pads and tungsten carbide burr attachments, respectively. Migration was evaluated using water and 3% acetic acid as food simulants. Low concentrations of silver (Ag) were detected in water simulants, a small portion (<4 ng dm-2) in the form of silver nanoparticles (AgNPs) with particle number concentrations on the order of 106 particles dm-2. Median particle diameter was 40 nm. Nanoparticle release into water was observed under all five consumer use scenarios studied, however there was no correlation with the different levels of stress simulated.

Environmental release of core-shell semiconductor nanocrystals from free-standing polymer nanocomposite films.

Concomitant with the development of polymer nanocomposite (PNC) technologies across numerous industries is an expanding awareness of the uncertainty with which engineered nanoparticles embedded within these materials may be released into the external environment, particularly liquid media. Recently there has been an interest in evaluating potential exposure to nanoscale fillers from PNCs, but existing studies often rely upon uncharacterized, poor quality, or proprietary materials, creating a barrier to making general mechanistic conclusions about release phenomena. In this study we employed semiconductor nanoparticles (quantum dots, QDs) as model nanofillers to quantify potential release into liquid media under specific environmental conditions. QDs of two sizes were incorporated into low-density polyethylene by melt compounding and the mixtures were extruded as free-standing fluorescent films. These films were subjected to tests under conditions intended to accelerate potential release of embedded particles or dissolved residuals into liquid environments. Using inductively-coupled plasma mass spectrometry and laser scanning confocal microscopy, it was found that the acidity of the external medium, exposure time, and small differences in particle size (on the order of a few nm) all play pivotal roles in release kinetics. Particle dissolution was found to play a major if not dominant role in the release process. This paper also presents the first evidence that internally embedded nanoparticles contribute to the mass transfer, an observation made possible via the use of a model system that was deliberately designed to probe the complex relationships between nanoparticle-enabled plastics and the environment.

Surface Degradation and Nanoparticle Release of a Commercial Nanosilica/Polyurethane Coating Under UV Exposure.

Many coatings properties such as mechanical, electrical, and ultra violet (UV) resistance are greatly enhanced by the addition of nanoparticles, which can potentially increase the use of nanocoatings for many outdoor applications. However, because polymers used in all coatings are susceptible to degradation by weathering, nanoparticles in a coating may be brought to the surface and released into the environment during the life cycle of a nanocoating. Therefore, the goal of this study is to investigate the process and mechanism of surface degradation and potential particle release from a commercial nanosilica/polyurethane coating under accelerated UV exposure. Recent research at the National Institute of Standards and Technology (NIST) has shown that the matrix in an epoxy nanocomposite undergoes photodegradation during exposure to UV radiation, resulting in surface accumulation of nanoparticles and subsequent release from the composite. In this study, specimens of a commercial polyurethane (PU) coating, to which a 5 mass % surface treated silica nanoparticles solution was added, were exposed to well-controlled, accelerated UV environments. The nanocoating surface morphological changes and surface accumulation of nanoparticles as a function of UV exposure were measured, along with chemical change and mass loss using a variety of techniques. Particles from the surface of the coating were collected using a simulated rain process developed at NIST, and the collected runoff specimens were measured using inductively coupled plasma-optical emission spectroscopy (ICP-OES) to determine the amount of silicon released from the nanocoatings. The results demonstrated that the added silica nanoparticle solution decreased the photodegradation rate (i.e., stabilization) of the commercial PU nanocoating. Although the degradation was slower than the previous nanosilica epoxy model system, the degradation of the PU matrix resulted in accumulation of silica nanoparticles on the nanocoating surface and release to the environment by simulated rain. These experimental data are valuable for developing models to predict the long-term release of nanosilica from commercial PU nanocoatings used outdoors and, therefore, are essential for assessing the health and environmental risks during the service life of exterior PU nanocoatings.

Revealing the interface in polymer nanocomposites.

The morphological characterization of polymer nanocomposites over multiple length scales is a fundamental challenge. Here, we report a technique for high-throughput monitoring of interface and dispersion in polymer nanocomposites based on Förster resonance energy transfer (FRET). Nanofibrillated cellulose (NFC), fluorescently labeled with 5-(4,6-dichlorotriazinyl)-aminofluorescein (FL) and dispersed into polyethylene (PE) doped with Coumarin 30 (C30), is used as a model system to assess the ability of FRET to evaluate the effect of processing on NFC dispersion in PE. The level of energy transfer and its standard deviation, measured by fluorescence spectroscopy and laser scanning confocal microscopy (LSCM), are exploited to monitor the extent of interface formation and composite homogeneity, respectively. FRET algorithms are used to generate color-coded images for a real-space observation of energy transfer efficiency. These images reveal interface formation at a nanoscale while probing a macroscale area that is large enough to be representative of the entire sample. The unique ability of this technique to simultaneously provide orientation/spatial information at a macroscale and nanoscale features, encoded in the FRET signal, provides a new powerful tool for structure-property-processing investigation in polymer nanocomposites.