The visualization of phase separation in immiscible polymer blends holds significant industrial and academic relevance, as the resultant phase architecture governs the macroscopic properties and ultimate performance of blended materials. To address this challenge, a dual-fluorophore labeling strategy is introduced, enabling high-contrast differentiation of polymeric phases. By covalently tethering two spectrally orthogonal fluorophores to their respective polymer components, unambiguous spatial resolution of blend morphologies is achieved through laser scanning confocal microscopy (LSCM). When compatibilizers are incorporated, LSCM imaging reveals fundamentally reconfigured phase architectures compared to uncompatibilized systems. This fluorescence-based approach permits direct assessment of blend compatibility through quantitative evaluation of interfacial domain coherence and phase dispersion homogeneity. The methodology demonstrates exceptional versatility, successfully resolving phase boundaries in both chemically dissimilar systems (e.g., polylactic acid [PLA]/poly (butylene adipate-co-terephthalate) [PBAT] blends with pronounced polarity disparities) and structurally congruent polymers (e.g., polyethylene [PE]/polypropylene [PP] variants). The universal applicability stems from the substantial spectral distinction between fluorophore-labeled polymers, independent of variations in polymer polarity or structural configurations.
| [1] |
C. Koning, M. Van Duin, C. Pagnoulle, and R. Jerome, “Strategies for Compatibilization of Polymer Blends,” Progress in Polymer Science 23 (1998): 707–757.
|
| [2] |
C. W. Clarke, T. Sandmeier, K. A. Franklin, et al., “Dynamic Crosslinking Compatibilizes Immiscible Mixed Plastics,” Nature 616 (2023): 731–739.
|
| [3] |
T. Han, C. Gui, J. W. Y. Lam, et al., “High-Contrast Visualization and Differentiation of Microphase Separation in Polymer Blends by Fluorescent AIE Probes,” Macromolecules 50 (2017): 5807–5815.
|
| [4] |
T.-W. Lin, O. Padilla-Vélez, P. Kaewdeewong, A. M. LaPointe, G. W. Coates, and J. Eagan, “Advances in Nonreactive Polymer Compatibilizers for Commodity Polyolefin Blends,” Chemical Reviews 124 (2024): 9609–9632.
|
| [5] |
J. M. Eagan, J. Xu, R. Di Girolamo, et al., “Combining Polyethylene and Polypropylene: Enhanced Performance With PE/ i PP Multiblock Polymers,” Science 355 (2017): 814–816.
|
| [6] |
M. Kränzlein, S. Cui, J. Hu, A. M. LaPointe, B. P. Fors, and G. W. Coates, “One-Step Radical-Induced Synthesis of Graft Copolymers for Effective Compatibilization of Polyethylene and Polypropylene,” Journal of the American Chemical Society 147 (2025): 19052–19060.
|
| [7] |
C. Zou, J. Chen, M. A. Khan, G. Si, and C. Chen, “Stapler Strategies for Upcycling Mixed Plastics,” Journal of the American Chemical Society 146 (2024): 19449–19459.
|
| [8] |
W. Zhang, S. Chen, X. Lu, and Y. Liu, “On-Demand Nonalternating Copolymerization Enables Upcycling of Mixed Polyethylene and Nylon Plastics,” Journal of the American Chemical Society 147 (2025): 36254–36265.
|
| [9] |
H. L. He and F. X. Liang, “Interfacial Engineering of Polymer Blend With Janus Particle as Compatibilizer,” Chinese Journal of Polymer Science 41 (2023): 500–515.
|
| [10] |
J. W. Zou, T. T. Wang, L. S. Wu, et al., “Dynamically Cross-Linked Polyolefin Elastomers With Disulfide Bonds Fabricated by Free-Radical Reactive Processing,” Macromolecular Chemistry and Physics 226 (2025): e00133.
|
| [11] |
K. Yokoyama and Z. Guan, “A Vitrimer Acts as a Compatibilizer for Polyethylene and Polypropylene Blends,” Angewandte Chemie International Edition 63 (2024): e202317264.
|
| [12] |
J. Chen, W. Wang, C. Zou, and C. Chen, “Mechanical Recycling of Mixed Plastics by Supramolecular Dynamic Cross-Linking Strategy,” Journal of the American Chemical Society 147 (2025): 24747–24758.
|
| [13] |
W. Wen, C. Y. Li, X. Meng, W. G. Gong, S. Y. Chen, and Z. Xin, “Study on Compatibility of a Novel Cardanol-Based Compatibilizer in PLA/PBAT Blend,” Industrial & Engineering Chemistry Research 63 (2024): 8684–8696.
|
| [14] |
H. Wang, H. Tian, and S. Zhang, “Excellent Compatibilization Effect of a Dual Reactive Compatibilizer on the Immiscible MVQ/PP Blends,” Chinese Journal of Polymer Science 41 (2023): 1133–1141.
|
| [15] |
Y. Han, J. Shi, L. Mao, Z. Wang, and L. Zhang, “Improvement of Compatibility and Mechanical Performances of PLA/PBAT Composites With Epoxidized Soybean Oil as Compatibilizer,” Industrial & Engineering Chemistry Research 59 (2020): 21779–21790.
|
| [16] |
H. Pan, Z. Li, J. Yang, et al., “The Effect of MDI on the Structure and Mechanical Properties of Poly(Lactic Acid) and Poly(Butylene Adipate-co -Butylene Terephthalate) Blends,” RSC Advances 8 (2018): 4610–4623.
|
| [17] |
P. Ma, X. Cai, Y. Zhang, et al., “In-Situ Compatibilization of Poly(Lactic Acid) and Poly(Butylene Adipate-co-Terephthalate) Blends by Using Dicumyl Peroxide as a Free-Radical Initiator,” Polymer Degradation and Stability 102 (2014): 145–151.
|
| [18] |
T. Vialon, H. Sun, G. J. M. Formon, et al., “Upcycling Polyolefin Blends Into High-Performance Materials by Exploiting Azidotriazine Chemistry Using Reactive Extrusion,” Journal of the American Chemical Society 146 (2024): 2673–2684.
|
| [19] |
J. Castro, X. Westworth, R. Shrestha, K. Yokoyama, and Z. Guan, “Efficient and Robust Dynamic Crosslinking for Compatibilizing Immiscible Mixed Plastics Through In Situ Generated Singlet Nitrenes,” Advanced Materials 36 (2024): 2406203.
|
| [20] |
E. K. Neidhart, M. Hua, Z. Peng, et al., “C–H Functionalization of Polyolefins to Access Reprocessable Polyolefin Thermosets,” Journal of the American Chemical Society 145 (2023): 27450–27458.
|
| [21] |
C. R. López-Barrón and A. H. Tsou, “Strain Hardening of Polyethylene/Polypropylene Blends via Interfacial Reinforcement With Poly(Ethylene-cb-Propylene) Comb Block Copolymers,” Macromolecules 50 (2017): 2986.
|
| [22] |
J. Xu, G. Zhang, Y. Rong, and Y. Huang, “Study on the Ultraviolet Nanosecond Laser Ablation and Heat-Affected Zone of Polydimethylsiloxane Films Based on Comprehensive Surface Analysis,” Optics & Laser Technology 167 (2023): 109769.
|
| [23] |
A. A. Moud, “Polymer Blends Analyzed With Confocal Laser Scanning Microscopy,” Polymer Bulletin 80 (2023): 5929–5964.
|
| [24] |
Z. Qiu, X. Liu, J. W. Y. Lam, and B. Z. Tang, “The Marriage of Aggregation-Induced Emission With Polymer Science,” Macromolecular Rapid Communications 40 (2019): 1800568.
|
| [25] |
S. Ge, E. Wang, J. Li, and B. Z. Tang, “Aggregation-Induced Emission Boosting the Study of Polymer Science,” Macromolecular Rapid Communications 43 (2022): 2200080.
|
| [26] |
X. Wu and C. Barner-Kowollik, “Fluorescence-Readout as a Powerful Macromolecular Characterisation Tool,” Chemical Science 14 (2023): 12815–12849.
|
| [27] |
Ö. Pekcan and D. Kaya, “Fast Transient Fluorescence Technique for Studying Sol–Gel Phase Transition in Polymeric Mixtures,” Materials Chemistry and Physics 85 (2004): 137–144.
|
| [28] |
H. Kang, S. Park, B. Lee, J. Ahn, and S. Kim, “Modification of a Nile Red Staining Method for Microplastics Analysis: A Nile Red Plate Method,” Water 12 (2020): 3251.
|
| [29] |
C. J. Ellison and J. M. Torkelson, “Sensing the Glass Transition in Thin and Ultrathin Polymer Films via Fluorescence Probes and Labels,” Journal of Polymer Science Part B: Polymer Physics 40 (2002): 2745–2758.
|
| [30] |
S. Liu, Y. Cheng, H. Zhang, et al., “In Situ Monitoring of RAFT Polymerization by Tetraphenylethylene-Containing Agents With Aggregation-Induced Emission Characteristics,” Angewandte Chemie International Edition 57 (2018): 6274–6278.
|
| [31] |
J.-H. Xin, B.-B. Guo, C. Liu, et al., “AIE-Enabled In Situ and Real-Time Visualization of Polymer Growth During Interfacial Polymerization,” Macromolecules 56 (2023): 5415–5423.
|
| [32] |
S. Bao, Q. Wu, W. Qin, et al., “Sensitive and Reliable Detection of Glass Transition of Polymers by Fluorescent Probes Based on AIE Luminogens,” Polymer Chemistry 6 (2015): 3537–3542.
|
| [33] |
J. L. Wu, C. Zhang, W. Qin, D. P. Quan, M. L. Ge, and G. D. Liang, “Thermoresponsive Fluorescent Semicrystalline Polymers Decorated With Aggregation Induced Emission Luminogens,” Chinese Journal of Polymer Science 37 (2019): 394–400.
|
| [34] |
Z. Qiu, E. K. K. Chu, M. Jiang, et al., “A Simple and Sensitive Method for an Important Physical Parameter: Reliable Measurement of Glass Transition Temperature by AIEgens,” Macromolecules 50 (2017): 7620–7627.
|
| [35] |
J. L. Belmonte-Vázquez, Y. A. Amador-Sánchez, L. A. Rodríguez-Cortés, and B. Rodríguez-Molina, “Dual-State Emission (DSE) in Organic Fluorophores: Design and Applications,” Chemistry of Materials 33 (2021): 7160–7184.
|
| [36] |
A. Huber, J. Dubbert, T. D. Scherz, and J. Voskuhl, “Frontispiece: Design Concepts for Solution and Solid-State Emitters – A Modern Viewpoint on Classical and Non-Classical Approaches,” Chemistry – A European Journal 29 (2023): e2022024.
|
| [37] |
K. Li, Y. Zhu, B. Yao, et al., “Rotation-Restricted Thermally Activated Delayed Fluorescence Compounds for Efficient Solution-Processed OLEDs With EQEs of up to 24.3% and Small Roll-Off,” Chemical Communications 56 (2020): 5957–5960.
|
| [38] |
W. Dai, P. Liu, S. Guo, et al., “Triphenylquinoline (TPQ)-Based Dual-State Emissive Probe for Cell Imaging in Multicellular Tumor Spheroids,” ACS Applied Bio Materials 2 (2019): 3686.
|
| [39] |
D. Xi, Y. Xu, R. Xu, et al., “A Facilely Synthesized Dual-State Emission Platform for Picric Acid Detection and Latent Fingerprint Visualization,” Chemistry – A European Journal 26 (2020): 2741–2748.
|
| [40] |
Y. Ni, S. Zhang, X. He, et al., “Dual-State Emission Difluoroboron Derivatives for Selective Detection of Picric Acid and Reversible Acid/Base Fluorescence Switching,” Analytical Methods 13 (2021): 2830–2835.
|
| [41] |
J. Zhang, A. Konsmo, A. Sandberg, et al., “Phenolic Bis-Styrylbenzo[c]-1,2,5-Thiadiazoles as Probes for Fluorescence Microscopy Mapping of Aβ Plaque Heterogeneity,” Journal of Medicinal Chemistry 62 (2019): 2038–2048.
|
| [42] |
Z. Yu, Y. Yu, J. Jiang, L. Qin, and D. Hu, “Fluoro Substitution Effect on 2,1,3-Benzothiadiazole-Based Hybridized Local and Charge Transfer State Fluorophores for High-Performance Organic Light-Emitting Diodes,” Dyes and Pigments 213 (2023): 111184.
|
| [43] |
R. Liu, C. Zhou, Q. Ding, et al., “Dual-State Emission of D-A-D Type Benzothiadiazole Derivatives for the Sensitive Detection of Amine Compounds,” Dyes and Pigments 219 (2023): 111588.
|
| [44] |
S. Yang, S. Yi, J. Yun, et al., “Carbene-Mediated Polymer Cross-Linking With Diazo Compounds by C–H Activation and Insertion,” Macromolecules 55 (2022): 3423–3429.
|
| [45] |
S. Yi, S. Yang, Z. Xie, J. Yun, and X. Pan, “Carbene-Mediated Polymer Modification Using Diazo Compounds Under Photo or Thermal Activation Conditions,” ACS Macro Letters Journal 13 (2024): 711–718.
|
| [46] |
B. D. Schwarz, J. R. Denton, Y. Lian, H. M. L. Davies, and C. M. Williams, “Asymmetric [4 + 3] Cycloadditions Between Vinylcarbenoids and Dienes: Application to the Total Synthesis of the Natural Product (−)-5- epi -Vibsanin E,” Journal of the American Chemical Society 131 (2009): 8329–8332.
|
| [47] |
T. Yoshida, F. Yoshizawa, M. Itoh, T. Matsunaga, M. Watanabe, and M. Tamura, “Prediction of Fire and Explosion Hazards of Reactive Chemicals (Part 1). Estimation of Explosive Properties of Self-Reactive Chemicals From SC-DSC Data,” Kogyo Kayaku 48 (1987): 311.
|
| [48] |
M. Röttger, T. Domenech, R. van der Weegen, A. Breuillac, R. Nicolaÿ, and L. Leibler, “High-Performance Vitrimers From Commodity Thermoplastics Through Dioxaborolane Metathesis,” Science 356 (2017): 62–65.
|
RIGHTS & PERMISSIONS
2025 The Author(s). Aggregate published by SCUT, AIEI, and John Wiley & Sons Australia, Ltd.
PDF
