Polymer Molecular Weight Research Articles

Polymer Coated Polymeric (PCP) Microneedles for Controlled Delivery of Drugs (Dermal and Intravitreal)

Microneedles are used to deliver drugs topically across the skin and mucous membranes. Dissolvable microneedles are made using soluble polymers, which disintegrates in the tissue and release the entire payload instantaneously including the polymer construct. Often, a slow release of drug into the tissue is desirable to overcome the severity of side effects at the site of administration as well as systemic adverse effects. In addition, controlled release of active pharmaceutical ingredient (API) only (not the excipients) is safe and effective particularly when the drug delivery is intended to sensitive organs like the eye. In this project, the feasibility of fabricating polymer coated polymeric (PCP) microneedles to achieve a gradual release of only the active ingredient from the device was investigated. The potential application of such PCP microneedles in the dermal and intravitreal drug delivery was also explored using animal tissue models. The PCP microneedles were found to be intact even after prolonged contact with the release medium. The time at which 50% (T50%) of dextran (10 K) was released in case of microneedles prepared using 20% of core polymer (PVP-K30) was about 15 min versus less than 5 min in the case of uncoated microneedles. Whereas when the core polymer concentration was increased to 50%, the T50% was increased to 90 min. The rate of release depended on the polymer molecular weight grade. The rate of drug release was not influenced by the total amount of concentration of dextran. The PCP microneedles of lidocaine hydrochloride could constantly release the drug for up to 9 h in the skin tissue. Likewise, the PCP microneedles infused voriconazole, intravitreally for 6 h.

Polymer-monomer particles formation and particle size distribution during heterophase polymerization in the presence of water-insoluble organosilicon surfactant

In this work mechanism of polymer particles formation during styrene heterophase polymerization in the presence of waterinsoluble organosilicon surfactant was investigated. Dependency between monomer conversion rate from early stages of polymerization and particle diameters change, molecular weight, particle size and molecular weight distribution was analyzed. The effect of the gel effect and Ostwald maturation on particle diameter and polymer molecular weight was evaluated.

Amylose Inter-Chain Entanglement and Inter-Chain Overlap Impact Rice Quality.

Retrogradation of cooked rice happens in two ways: one is by the formation of ordered structures, and the other is through intra- and inter-chain entanglement and inter-chain overlap, which in turn are affected by the amylose chain-length distribution. Both entanglement and overlap could affect rice texture. Here, four amylose samples were isolated from starch by precipitation from a dimethyl sulfoxide solution with butan-1-ol and isoamyl alcohol. Following enzymatic debranching, they were then characterized using size-exclusion chromatography. Amylose solutions (10%, m/v) were made by dissolving amylose in 90% (v/v) DMSO. Amylose gels (10%, w/v) were made by dissolving amylose powders into hot water, followed by cooling. The rigidity of the amylose gels and the structural order were measured using a texture analyzer and X-ray diffractometer, respectively. In the amylose solution, for a given mass of polymer in a fixed amount of solvent, the total occupied volume was reduced when the polymer molecular weight was smaller, resulting in less inter-chain overlap and a lower viscosity of the amylose solution. The overall mobility and diffusion of the molecules were inversely related to the square of the molecular weight until the gelation concentration. Thus, amylose gels in which amylose had a lower molecular weight had a greater chance to permeate into other molecules, which counterintuitively led to more inter-chain entanglement and more rigid amylose gels during retrogradation. This information could help rice breeders improve rice quality by using the molecular structure of starch as a guide.

The effect of polymer grafting on the mechanical properties of PEG‐grafted cellulose nanocrystals in poly(lactic acid)

AbstractPoly(lactic acid) (PLA) is a commercially available bio‐based polymer that is a potential alternative to many commodity petrochemical‐based polymers. However, PLA's thermomechanical properties limit its use in many applications. Incorporating polymer‐grafted cellulose nanocrystals (CNCs) is one potential route to improving these mechanical properties. One key challenge in using these polymer‐grafted nanoparticles is to understand which variables associated with polymer grafting are most important for improving composite properties. In this work, poly(ethylene glycol)‐grafted CNCs are used to study the effects of polymer grafting density and molecular weight on the properties of PLA composites. All CNC nanofillers are found to reinforce PLA above the glass transition temperature, but non‐grafted CNCs and CNCs grafted with short PEG chains (<2 kg mol−1) are found to cause significant embrittlement, generally resulting in less than 3% elongation‐at‐break. By grafting higher molecular weight PEG (10 kg mol−1) onto the CNCs at a grafting density where the polymer chains are predicted to be in the semi‐dilute polymer brush conformation (~0.1 chains nm−2), embrittlement can be avoided.

Hot melt extruded PLGA implants loaded with ibuprofen: How heat exposure alters the physical drug state

Hot melt extrusion offers an interesting potential for the manufacturing of poly(lactic-co-glycolic acid) (PLGA)-based implants. However, the heat treatment might substantially alter the polymer, drug and degree of drug-polymer mixing. The aim of this study was to better understand the impact of varying the exposure time to 105 °C in the case of ibuprofen-loaded PLGA implants. In vitro drug release was measured in phosphate buffer pH 7.4. Optical and scanning electron microscopy, DSC, GPC, X-ray diffraction as well as gravimetric analysis were used to monitor dynamic changes of the implants’ morphology, dry & wet mass and average polymer molecular weight. Interestingly, increasing the exposure time from 3 to 15 min led to a decrease in the amount of crystalline drug present in the system, resulting in a slight decrease in the initial burst release. The average PLGA molecular weight also slightly decreased during the heat treatment. In contrast, the relatively rapid penetration of water into the implant and subsequent polymer degradation throughout the device did not seem to be affected to a noteworthy extent. Also the onset of substantial implant swelling after about 1 week and the subsequent beginning of the final rapid drug release phase (accounting for about 80% of the total drug dose) were not significantly altered. Thus, in this study, the changes in the physical state of the drug in the implant induced by prolonged heat exposure had only a limited impact on system performance. However, for different drugs and polymers, changes in their physical state as a function of the heat exposure time might have more importance consequences. Careful monitoring of these kinetic aspects is recommended to assure desired product quality.

Rigidity-Tuned Full-Color Emission: Uncommon Luminescence Change from Polymer Free-Volume Variations.

Probing the rigidity change of microenvironments via tracking embedded molecular fluorophore emissions represents a robust approach to monitor various polymer microstructural evolutions and biomolecular events with a high spatiotemporal resolution. However, reported fluorophores exclusively blueshift their emissions (termed as "rigidochromism") or merely alter intensities upon rigidification, suffering from inferior sensitivities, low-contrast outputs, and attenuated biocompatibilities. Here, phenanthridine-fused triazatruxene fluorophores (PTFs) with pronounced bathochromic emission (up to 135nm) toward rigidifying media at a low loading of 5ppm without sacrificing the quantum yields and lifetime are developed. PTFs effectively interact with polymeric matrixes through polar-π interactions and form charge-transfer complexes, resulting to a remarkable fluorescent color change from blue to red-orange over matrix rigidifying. Such a unique anti-rigidochromism enables a highly sensitive rigidity detection (i.e., a subtle polymer molecular-weight change (as low as 1000Da vs up to 10kDa for conventional probes) can result to obvious emission color changes). PTFs are able to noninvasively detect polymerization kinetics and in situ optically report polymer degradations. The broadly (nearly full-spectrum) tunable emission and the efficient coupling between anti-rigidochromism and polymer hierarchical structures/topologies render fluorescence with controlled wavelength and chirality, leading to an unprecedented free-volume-based data encryption and anti-counterfeiting technology with a superhigh security level.

Poly(arylene sulfide)s via nucleophilic aromatic substitution reactions of halogenated pyromellitic diimides

AbstractNucleophilic aromatic substitution (SNAr) reactions are exploited to prepare poly(arylene sulfide)s (PAS's) via the reaction of bis‐thiolates and dibrominated pyromellitic diimide (PMDI) derivatives. Small‐molecule model studies reveal the reaction is well‐defined and proceeds in quantitative yield in practical times at room temperature. Variation in comonomer feed ratios allowed some control over target polymer molecular weights in the step polymerization, but control was likely limited by the relatively poor polymer solubility in the dipolar aprotic solvents typically employed to promote SNAr reactions. One substitution pattern produces a steric “pocket” around the PMDI units, inducing a peculiar solubility trend in halogenated solvents; that is, greatly reduced solubility in CHCl3 relative to CH2Cl2 and C2H2Cl4. One example small‐molecule readily dissolves in CHCl3 at room temperature, then rapidly grows poorly soluble crystals revealed by single‐crystal XRD to contain CHCl3 molecules in the steric pockets. Finally, the recently demonstrated depolymerization of phthalonitrile‐based PAS's via ipso substitution with monothiolates as chain scission agents yields quantitative molecular weight reduction to monomeric species from the polymers reported here.

Optimizing the surface properties of nanofiltration membrane by tailoring the diffusion coefficient of amine monomer

High-performance hollow fiber NF membranes with network structure were successfully prepared by introducing macromolecular polyvinyl alcohol (PVA) into aqueous phase to change the diffusion coefficient of amine monomer (piperazine, PIP) in organic phase. Based on Wilke-Change equation, a theoretical model (DAO) dealing with viscosity of aqueous phase, molecular weight of PVA, and diffusion coefficient of amine monomer in organic phase was proposed. The applicability of the DAO model was verified by ultraviolet spectrophotometry (UV) monitoring and one-dimensional diffusion model. Subsequently, the structure of NF membranes was analyzed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results suggested that the diffusion coefficient of amine monomer was negatively correlated with aqueous phase's viscosity and polymer's molecular weight. With PVA205 (Molecular weight is 205000 Da) used to change the viscosity of aqueous phase, the diffusion coefficient of PIP (in n-hexane) was close to 2.70 × 10−6 cm2/s, and the resultant NF membrane (NF-PVA205-1) showed excellent performance; specifically, NF-PVA205-1 achieved a flux as 107 L/m2·h (4 bar), which is 3.5-times higher than that of pure polyamide NF membrane, and the rejection rate for sodium sulfate can reach 97.9%. Such a facile fabrication method proposed in this study can balance the "trade-off" effect of traditional NF membrane.

Donor–Acceptor Stenhouse Adduct‐Polydimethylsiloxane‐Conjugates for Enhanced Photoswitching in Bulk Polymers

Donor-acceptor Stenhouse adducts (DASAs) are a rapidly emerging class of visible light-activated photochromes and DASA-functionalized polymers hold great promise as biocompatible photoresponsive materials. However, the photoswitching performance of DASAs in solid polymer matrices is often low, particularly in materials below their glass transition temperature. To overcome this limitation, DASAs are conjugated to polydimethylsiloxanes which have a glass transition temperature far below room temperature and which can create a mobile molecular environment around the DASAs for achieving more solution-like photoswitching kinetics in bulk polymers. The dispersion of DASAs conjugated to such flexible oligomers into solid polymer matrices allows for more effective and tunable DASA photoswitching in stiff polymers, such as poly(methyl methacrylate), without requiring modifications of the matrix. The photoswitching of conjugates with varying polymer molecular weight, linker type, and architecture is characterized via time-dependent UV-vis spectroscopy in organic solvents and blended into polymethacrylate films. In addition, DASA-functionalized polydimethylsiloxane networks, accessible via the same synthetic route, provide an alternative solution for achieving fast and efficient DASA photoswitching in the bulk owing to their intrinsic softness and flexibility. These findings may contribute to the development of DASA-functionalized materials with better tunable, more effective, and more reversible modulation of their optical properties.

Effect of Tm of blend components on the isothermal melt-crystallization process of PHB/PLLA blends investigated using spectroscopic imaging and DSC

The understanding of morphology and crystallization in biopolymer blends offers the ability to tune these properties for specific uses. In this study, the isothermal melt-crystallization process of poly (3-hydroxybutyrate) (PHB)/poly ( l -lactic acid) (PLLA) blends with different weight loadings and molecular weights was investigated using in-situ attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopic imaging and differential scanning calorimetry (DSC). When the isothermal crystallization temperature is constant, increasing the fraction of blend component with a lower T m results in the decreasing T m of both blend components, which is indicated in DSC thermograms. The reduced T m delays the crystallization of both blend components and then the restrained crystallization leads to a greater extent of phase separation, which is shown in ATR-FTIR spectroscopic images. Likewise, at a constant isothermal crystallization temperature, with the decreasing molecular weights of blend components, the miscibility of polymer blend should be enhanced because of the shift of the phase boundary in phase diagram to lower temperatures. However, the decreasing overall crystallization rate and the delay of crystallization indicated in the integrated absorbance profiles and the decreasing T m indicated in the DSC thermograms can be used to explain the greater extent of phase separation in the PHB/PLLA blend shown in the spectroscopic images. A phase diagram was prepared to show the effect of polymer molecular weight on the miscibility of PHB/PLLA blends. Thus, increasing the fraction of the blend component with a higher T m , choosing polymers with a higher molecular weight and decreasing the isothermal crystallization temperature have been demonstrated to be effective methods to promote the miscibility of upper critical solution temperature (UCST) crystallizable polymer blends. Moreover, it was concluded that in-situ ATR-FTIR spectroscopic imaging can be combined with integrated absorbance profiles and DSC thermograms to deepen the understanding of multicomponent polymer systems. • A phase diagram was prepared to show the effect of M w on the miscibility of PHB/PLLA blends. • Effective methods are found to promote the miscibility of UCST polymer blends during isothermal crystallization process. • Spectroscopic imaging can be combined with DSC thermograms to deepen the understanding of multicomponent polymer systems.

In vitro mucoadhesive properties of hydrophilic polymers: Effects of contact time, disk shape, and molecular weight

AbstractThis study aimed to investigate the effects of various factors, including contact time, disk shape, and polymer molecular weight, on the in vitro mucoadhesive properties of disks prepared using hydrophilic polymers. Mucoadhesive performance was evaluated by measuring the peak detachment force and work of adhesion values using tensile tests. The mucoadhesive force and work of adhesion values increased with increasing contact time between the polymeric disks and mucin gel layer until 60 s. Increased mucoadhesive performances were typically observed when the disks comprised high‐molecular‐weight polymers, which indicates the increase in the entanglement. Increasing the thicknesses of the disks allowed the disks to absorb more water and thereby have more flexible polymeric chains, enhancing the mucoadhesive capacity. The proportional increase in the mucoadhesive force and work values were observed with increasing the surface areas of the disks. In conclusion, this study comprehensively demonstrated the effects of various experimental factors on mucoadhesion.

Significance of polymer elasticity on drag reduction performance in dispersed oil-in-water pipe flow

Mechanisms proposed for the drag reduction by high molecular weight polymers range from stress anisotropy, elasticity and the formation of intermolecular associations. This experimental study tests the role of elasticity as indicated by the measurement of normal force, from which Weissenberg number can be calculated. Cationic drag reducing polyacrylamides were injected in a dispersed oil-in-water flow through 30.6-mm pipe. Four polymers were used to investigate the effect of polymer molecular weight and charge density. Three polymers with different molecular weights and 10% charge density were investigated along with a polymer with 45% charge density. The flow in the test section was set at 0.3 oil fraction and mixture velocities of 0.8, 1.0, 1.2 and 1.5 m/s (Reynolds number above 34,400) with polymer concentrations from 10 to 40 ppm. Generally, the maximum drag reduction was obtained for polymer concentrations in the test section higher than 20 ppm. It increased with flow velocity and polymer molecular weight. The rheological measurements indicated that the elasticity of the polymers increase with the increase in molecular weight and change density. Similarly, the maximum drag reduction increased with the increase in molecular weight and charge density, which indicates a correlation between the efficiency of the drag reducing polymer and its elasticity. Drag reduction increased also with the increase in mixture velocity (or Reynolds number). On the other hand, drag reduction was generally independent of the hydrodynamic volume of the polymer above intrinsic viscosity of 4700 cm3/g.

Synergistic enhancement in optoelectrical anisotropy of polymer film at the air-liquid interface: An insight into molecular weight distribution dependent polymer alignment

In the context of polymer films, the degree of polymer chain orientation and alignment plays a crucial role in producing a high-performance electronic device owing to its quasi 1D nature. Therefore, a novel investigation on the dependency of optoelectrical anisotropy on polymer molecular weight distribution and its synergistic enhancement at the air-liquid interface was conducted using poly (3, 3′″ dialkylquarterthiophene)(PQT-12). We also explored PQT-12 (2:1), where 2:1 is the ratio by weight of the polymer obtained from hexane and CH2Cl2, respectively. In order to understand the mechanism of self-assembly and alignment of different molecular weight polymers at the air-liquid interface, Margonian flow effect was used to obtain oriented and aligned films that were investigated using multiple characterization techniques at the molecular, microscopic, and macroscopic levels. It was found that the film formed using PQT-12 (2:1) demonstrated a synergistic enhancement in dichroism (up to 55%), orientation, and ordering with synergistic enhancement in electrical anisotropy up to 11, mobility upto 11-fold and 2.5 fold respectively as compare to pristine PQT-12 (Hexane) and PQT-12 (CH2Cl2) isolated polymer in ambient condition. Thus, our study presents the an insight into the molecular weight distribution dependent alignment at air liquid interface for enhancement in device performance.

Regulation of Irradiation‐Dependent Long‐Lived Room Temperature Phosphorescence by Controlling Molecular Structures of Chromophores and Matrix

AbstractLong‐lived room temperature phosphorescent (LRTP) materials have attracted widespread attention due to their unique luminescence phenomenon and application prospects in the fields of information encryption and bioimaging. However, achieving intelligent response LRTP from amorphous polymers under atmospheric conditions is fascinating but challenging. Here, a series of irradiation‐dependent LRTP systems with ultralong phosphorescent lifetime and high quantum yields are fabricated by a consuming triplet oxygen strategy, and the LRTP performance exhibits obvious chromophore structure and polymeric molecular weight dependence. By extending the UV irradiation time, the phosphorescence lifetime can be increased by hundreds of times, which can exceed 2 s. Experimental results prove that the molecular weight of the polymer matrix, the doping concentration, and the structure of the chromophore have a crucial influence on the stimulus‐response speed and phosphorescence properties of the materials. This kind of intelligent and irradiation‐dependent LRTP material has excellent application prospects in the field of multi‐level information encryption. This work will effectively promote the development of stimulus‐responsive LRTP materials under atmospheric conditions.

Isospecific Polymerization of Halide- and Amino-Substituted Styrenes Using a Bis(phenolate) Titanium Catalyst

Isospecific polymerization of polar styrenes is a challenge of polymer science. Particularly challenging are monomers bearing electron-withdrawing substituents or bulky substituents. Here, we report the coordination polymerization of halide- and amino-functionalized styrenes including para-fluorostyrene (pFS), para-chlorostyrene (pClS), para-bromostyrene (pBrS), and para-(N,N-diethylamino)styrene (DMAS) using 2,2′-sulfur-bridged bis(phenolate) titanium precursor (1). The combination of 1 and [Ph3C][B(C6F5)4] and AliBu3 provides crystalline poly(pFS)s with perfect isotacticity (mmmm > 95%) and high molecular weights (≤16.0 × 104 g mol−1). Upon activation with a large excess of DMAO, 1 reaches polymerization activity of 5.58 × 105 g molTi−1 h−1 producing isotactic poly(pFS)s featuring higher molecular weights (≤39.6 × 104 g mol−1). The distinguished performance of the 1/DMAO system has been extended to the polymerization of pClS and pBrS, both usually involve halogen abstraction during the polymerization, to produce isotactic and high molecular weight (Mn = 32.2 × 104 vs. 13.7 × 104 g mol−1) polymers in good activities (2.18 × 105 vs. 1.31 × 105 g molTi−1 h−1). Surprisingly, 1/DMAO is nearly inactive for DMAS polymerization, on contrary, the system 1/[Ph3C][B(C6F5)4]/AliBu3 displays isoselectivity (mmmm > 95%) albeit in a moderate activity.

Impact assessment of the variables affecting the drug release and extraction of polyethylene oxide based tablets

The overall objective of this research is to investigate the impacts of the polymer's molecular weight and source on the abuse deterrent properties of the PEO-based promethazine hydrochloride (PMZ HCl) tablets. Formulations were manufactured by hot-melt extrusion and direct compression, followed by curing. Thermal and mechanical manipulation techniques were applied and compared to the intact tablets. The prime mechanism of the drug release was found to be represented by the diffusion-controlled mechanism and the first-order model for the direct compressed and the hot-melt extruded whole tablets, respectively. A robust Artificial Neural Network (ANN) model was built, and a significance testing analysis was performed to identify the criticality and the impact of the investigated variables on the % release of the active pharmaceutical ingredient (API). The results showed that the use of the polymer from different suppliers had the lowest impact on the % release per time point. Furthermore, we observed that the tablets produced by hot-melt extrusion had faster release rates than tablets produced by direct compression. Moreover, the extraction studies showed that the % API recovered from the hot-melt extruded tablets was significantly higher than the direct compressed tablets regardless of the polymer molecular weight. The findings were attributed to the polymer's thermal degradation during the hot-melt extrusion process, which caused a reduction in solution viscosity and crystallinity of the polymer. The syringeability studies showed that it was relatively harder to withdraw the solution from the DOW samples; however, the % recovered API was higher than samples containing the polymer from Sumitomo Seika.

A Strategy Based on Aggregation-Induced Ratiometric Emission to Differentiate Molecular Weight of Supramolecular Polymers.

Molecular weight has an important bearing on the properties of supramolecular polymers. However, the intuitive differentiation of the molecular weight of supramolecular polymers remains challenging. Given this situation, establishing a reliable relationship between fluorescence properties and molecular weight may be a promising strategy. Herein, we prepared a supramolecular monomer M1 with aggregation-induced ratiometric emission characteristics. With the increasing M1 concentration (0.100-100 mM), the average degree of polymerization (DPDOSY ) rose from 1.00 to 293. Meanwhile, the color changed from dark blue to cyan, finally to yellow-green in the same concentration range. Hence, the intuitive relationship between DPDOSY and fluorescence colors was constructed, allowing the visual differentiation of molecular weight. Moreover, the fluorescence color could be regulated by introducing a competitive molecule to induce the depolymerization of supramolecular polymers.

A Strategy Based on Aggregation‐Induced Ratiometric Emission to Differentiate Molecular Weight of Supramolecular Polymers

AbstractMolecular weight has an important bearing on the properties of supramolecular polymers. However, the intuitive differentiation of the molecular weight of supramolecular polymers remains challenging. Given this situation, establishing a reliable relationship between fluorescence properties and molecular weight may be a promising strategy. Herein, we prepared a supramolecular monomerM1with aggregation‐induced ratiometric emission characteristics. With the increasingM1concentration (0.100–100 mM), the average degree of polymerization (DPDOSY) rose from 1.00 to 293. Meanwhile, the color changed from dark blue to cyan, finally to yellow‐green in the same concentration range. Hence, the intuitive relationship between DPDOSYand fluorescence colors was constructed, allowing the visual differentiation of molecular weight. Moreover, the fluorescence color could be regulated by introducing a competitive molecule to induce the depolymerization of supramolecular polymers.

Influence of Levan on the Thermally Induced Gel Formation of β-Lactoglobulin

In this study, the influence of levan on the phase behavior and the thermally induced gelation of the mixed β-lactoglobulin—levan gels as a function of polymer content, molecular weight and ionic strength was characterized. For this purpose, rheology was used to study the mechanical properties of the gels and the water binding of the network structure was investigated by time domain nuclear magnetic resonance. Phase behavior and network type were analyzed by optical observation and electron microscopy. Levan enhanced the aggregation and gel formation of β-lg due to segregative forces between the polymer species. Segregation was caused by the excluded volume effect and was more pronounced at lower ionic strength, higher levan contents and higher levan molecular weights. The presence of levan increased the water binding of the gel networks. However, this effect decreased with increasing levan content. At high ionic strength and high levan content, phase separated gels were formed. While segregative forces enhanced network formation, and therefore, increased the gel strength of mixed gels at low ionic strength, levan had also antagonistic effects on the network formation at high ionic strength and high polymer contents.

Unraveling Amphiphilic Poly(N-vinylcaprolactam)/Water Interface by Nuclear Magnetic Resonance Relaxometry: Control of Clathrate Hydrate Formation Kinetics.

Water-soluble amphiphilic polymers are vital chemicals in the oil and gas industry to retard crystal growth of hydrocarbon hydrate via surface adsorption and suppress nucleation of a pristine hydrate nucleus, thereby preventing formation of hydrate blockages in flow lines during oil and natural gas production. Apart from a few theoretical modeling studies, an experimental method to study the polymer/water interface in the crystal growth is critically needed. Here, water motions in the hydration shells of an exemplary kinetic inhibitor, poly(N-vinylcaprolactam), during hydrate formation from the tetrahydrofuran/water system are revealed via nuclear magnetic resonance relaxometry. Unequivocal experiments show that the pivotal interfacial water in the tightly bound state gradually freezes at rates depending on the polymer molecular weight (MW). This is supported by nonfreezable water analysis, which is correlated to the inhibition time. The polymers tune the kinetics of the hydration process via interaction with and perturbation of the water molecules. The free water component in the polymer solution crystallizes at a very slow rate when in partially restricted mobility, whereas the bound water component increases in the reaction, with the polymer/water interface serving as the reaction sites. The appropriate MW (including average MW and polydispersity values) of the inhibitive polymers can give rise to maximal retardation of the hydrate crystal growth. This work will help control other multiphase crystallization kinetic processes through the design of inhibitors or promoters functioning in the interface.