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We utilize the lattice cluster theory (LCT) of polymer fluids to show that the configurational entropy, enthalpy, and internal energy are all closely interrelated, as suggested by recent measurements by Caruthers and Medvedev, so that the generalized entropy theory (GET) of glass formation, a combination of the LCT and Adam-Gibbs model, can be recast in terms of any of these thermodynamic properties as a matter of convenience. Thermodynamic scaling, a form of density-temperature scaling exhibited by dynamic and some thermodynamic properties, is used to assess which thermodynamic properties are most naturally linked to dynamics, and we explore the origin of this scaling by both direct calculations based on the GET and molecular dynamics simulations of a coarse-grained polymer model. Through a combination of our comprehensive modeling of thermodynamic properties using the LCT and the highly predictive GET model for how the fluid thermodynamics relate to its dynamics, along with simulation results confirming these theoretical frameworks, we obtain insights into thermodynamic aspects of collective motion and the slow $\beta$-relaxation processes of glass-forming liquids., Comment: 77 pages, 13 figures, accepted for publication in Macromolecules

We develop a theory for the motion of a particle grafted with inhomogeneous bead-spring Rouse chains via the generalized Langevin equation (GLE), where individual grafted polymers are allowed to take different bead friction coefficients, spring constants, and chain lengths. An exact solution of the memory kernel K(t) is obtained for the particle in the time (t) domain in the GLE, which depends only on the relaxation of the grafted chains. The t-dependent mean square displacement g(t) of the polymer-grafted particle is then derived as a function of the friction coefficient γ0 of the bare particle and K(t). Our theory offers a direct way to quantify the contributions of the grafted chain relaxation to the mobility of the particle in terms of K(t). This powerful feature enables us to clarify the effect on g(t) of dynamical coupling between the particle and grafted chains, leading to the identification of a relaxation time of fundamental importance in polymer-grafted particles, namely, the particle relaxation time. This timescale quantifies the competition between the contributions of the solvent and grafted chains to the friction of the grafted particle and separates g(t) into the particle- and chain-dominated regimes. The monomer relaxation time and the grafted chain relaxation time further divide the chain-dominated regime of g(t) into subdiffusive and diffusive regimes. Analysis of the asymptotic behaviors of K(t) and g(t) provides a clear physical picture of the mobility of the particle in different dynamical regimes, shedding light on the complex dynamics of polymer-grafted particles.

The generalized Langevin equation (GLE) provides an attractive theoretical framework for investigating the dynamics of conformational fluctuations of polymeric systems. While the memory kernel is a central function in the GLE, explicit analytical forms for this function have been challenging to obtain, even for the simple models of polymer dynamics. Here, we achieve an explicit analytical expression for the memory kernel in the GLE for the end-to-end vector of Rouse chains in the overdamped limit. Our derivation takes advantage of the finding that the dynamics of the end-to-end vector of Rouse chains with both free ends are equivalent to those of Rouse chains with one free end and the other fixed. For the latter model, we first show that the equations of motion of the Rouse modes as well as their statistical properties can be obtained under the boundary conditions where the free end is held fixed temporarily. We then analytically solve the terms associated with intrachain interactions in the GLE. By formally comparing these terms with the GLE based on the Rouse modes, we obtain an explicit expression for the memory kernel, along with analytical forms for the potential field and the random colored noise force. Our analytical memory kernel is confirmed by numerical calculations in the Laplace space and is shown to yield asymptotic behaviors that are consistent with previous studies. Finally, we utilize our analytical result to simulate the cyclization dynamics of Rouse chains and discuss the scaling of the cyclization time with chain length.

Numerous experiments reveal that the dynamics of glass-forming polymer melts are profoundly influenced by the application of pressure, but a fundamental microscopic understanding of these observations remains incomplete. We explore the structural relaxation of a model glass-forming polymer melt over a wide range of pressures (P) by molecular dynamics simulation. In accord with experiments for nonassociating polymer melts and the generalized entropy theory, we find that the P dependence of the structural relaxation time (τα) can be described by a pressure analog of the Vogel–Fulcher–Tammann equation and that the characteristic temperatures of glass formation increase with P, while the fragility decreases with P. Further, we demonstrate that τα for various P can quantitatively be described by the string model of glass formation, where the enthalpy and entropy of activation are found to be proportional, an effect that is expected to apply to polymeric materials under various applied fields.

The chain retraction hypothesis of the tube model for nonlinear polymer rheology has been challenged by the recent small-angle neutron scattering (SANS) experiment (Wang, Z.; Lam, C. N.; Chen, W.-R.; Wang, W.; Liu, J.; Liu, Y.; Porcar, L.; Stanley, C. B.; Zhao, Z.; Hong, K.; Wang, Y., Fingerprinting Molecular Relaxation in Deformed Polymers. Phys. Rev. X 2017, 7, 031003). In this work, we further examine the microscopic relaxation mechanism of entangled polymer melts after a large step uniaxial extension by using large-scale molecular dynamics simulation. We show that the unique structural features associated with the chain retraction mechanism of the tube model are absent in our simulations, in agreement with the previous experimental results. In contrast to SANS experiments, molecular dynamics simulations allow us to accurately and unambiguously determine the evolution of the radius of gyration tensor of a long polymer chain after a large step deformation. Contrary to the prediction of the tube model, o...

The influence of the monomer chemical structure and architecture on polymer glass formation has been long appreciated to be dominated by two principal molecular factors, namely, cohesive energy and...

We adopt Langevin dynamics to explore the stress-structure relationship of telechelic reversible associating polymer gel during startup shear flow, with shear strengths varying from Wi = 12.6 to Wi = 12640. At weak shear flow Wi = 12.6, the shear stress proportionally increases with shear strain at short times, followed by a strain hardening behavior and then passes through a maximum (σmax, γmax) and finally decreases until it reaches the steady state. During the evolution of stress, the gel network is only slightly broken and essentially maintains its framework, and the strain hardening behavior originates from the excessive stretching of chains. On the other hand, the stress-strain curve at intermediate shear flow Wi = 505.6 shows two differences from that at Wi = 12.6, namely, the absence of strain hardening and a dramatic increase of stress at large strains, which is caused by the rupture of gel network at small strains and the network recovery at large strains, respectively. Finally, at very strong shear flow Wi = 6319.7, the gel network is immediately broken by shear flow and the stress-strain curve exhibits similar behaviors to those of classical polymeric liquids.

The generalized entropy theory (GET) of glass formation provides an analytic framework for the structural relaxation time and thermodynamic properties of glass-forming polymers in terms of molecula...

Motivated by empirical observations suggesting that changes in the activation volume ΔV# upon varying temperature (T), determined from the pressure (P) dependence of the segmental structural relaxa...

The key role of chain flexibility in polymer glass formation has long been appreciated, but a fundamental understanding of how chain stiffness influences polymer glass formation remains elusive. In...

As the Burgers vector of a secondary dislocation may not conform to the translation vectors in the periodic pattern in a high-resolution transmission electron microscope (HRTEM) image, a Burgers circuit directly constructed according to an HRTEM image may render a wrong Burgers vector. The HRTEM images of the habit plane (HP) of δ precipitate in an Inconel 718 alloy were re-examined by using different Burgers circuits, as an example. Evidence is found for predicted secondary dislocation associated with a down step. The Burgers vector of the dislocation is 1 / 6 [ 11 2 ¯ ] γ / 1 / 3 [ 00 1 ¯ ] δ , determined with the Burgers circuit built on the reference of the displacement shift completely lattice (DSCL). It is consistent with both the calculated and the measured result of the major defects in the habit plane. Different Burgers vectors due to different Burgers circuits were explained quantitatively. The present study has a general implication for the determination of the Burgers vectors of secondary interfacial dislocations in other systems.

We show that thermodynamic scaling can be derived by combining the Murnaghan equation of state (EOS) with the generalized entropy theory (GET) of glass formation. In our theory, thermodynamic scaling arises in the non-Arrhenius relaxation regime as a scaling property of the fluid configurational entropy density $s_c$, normalized by its value $s_c^*$ at the onset temperature $T_A$ of glass formation, $s_c / s_c^*$, so that a constant value of $TV^{\gamma}$ corresponds to a \textit{reduced isoentropic} fluid condition. Molecular dynamics simulations on a coarse-grained polymer melt are utilized to confirm that the predicted thermodynamic scaling of $\tau_{\alpha}$ by the GET holds both above and below $T_A$ and to test whether the extent $L$ of stringlike collective motion, normalized its value $L_A$ at $T_A$, also obeys thermodynamic scaling, as required for consistency with thermodynamic scaling. While the predicted thermodynamic scaling of both $\tau_{\alpha}$ and $L/ L_A$ is confirmed by simulation, we find that the isothermal compressibility $\kappa_T$ and the long wavelength limit $S(0)$ of the static structure factor do not exhibit thermodynamic scaling, an observation that would appear to eliminate some proposed models of glass formation emphasizing fluid `structure' over configurational entropy. It is found, however, that by defining a low temperature hyperuniform reference state, we may define a compressibility relative to this condition, $\delta \kappa_T$, a transformed dimensionless variable that exhibits thermodynamic scaling and which can be directly related to $s_c / s_c^*$. Further, the Murnaghan EOS allows us to interpret $\gamma$ as a measure of intrinsic anharmonicity of intermolecular interactions that may be directly determined from the pressure derivative of the material bulk modulus., Comment: 77 pages, 14 figures

We provide a perspective on polymer glass formation, with an emphasis on models in which the fluid entropy and collective particle motion dominate the theoretical description and data analysis. We first discuss the dynamics of liquids in the high temperature Arrhenius regime, where transition state theory is formally applicable. We then summarize the evolution of the entropy theory from a qualitative framework for organizing and interpreting temperature-dependent viscosity data by Kauzmann to the formulation of a hypothetical `ideal thermodynamic glass transition' by Gibbs and DiMarzio, followed by seminal measurements linking entropy and relaxation by Bestul and Chang and the Adam-Gibbs (AG) model of glass formation rationalizing the observations of Bestul and Chang. These developments laid the groundwork for the generalized entropy theory (GET), which merges an improved lattice model of polymer thermodynamics accounting for molecular structural details and enabling the analytic calculation of the configurational entropy with the AG model, giving rise to a highly predictive model of the segmental structural relaxation time of polymeric glass-forming liquids. The development of the GET has occurred in parallel with the string model of glass formation in which concrete realizations of the cooperatively rearranging regions are identified and quantified for a wide range of polymeric and other glass-forming materials. The string model has shown that many of the assumptions of AG are well supported by simulations, while others are certainly not, giving rise to an entropy theory of glass formation that is largely in accord with the GET. As the GET and string models continue to be refined, these models progressively grow into a more unified framework, and this Perspective reviews the present status of development of this promising approach to the dynamics of polymeric glass-forming liquids., Comment: 108 pages, 14 figures

A 73-year-old man was hospitalized for arrhythmia and underwent intracardiac electrophysiologic examination and cryoablation treatment. Because of the complains of pain in the root of right thigh, he underwent arteriovenous ultrasound examination after interventional therapy. Ultrasound showed a heterogeneous mass on the posterolateral wall of the right common femoral vein ，which was mainly hypoechoic with small anechoic zone in the center. The pulsation of the anechoic area, the blood flow signal in it, and the characteristics of “to-and-fro” flow spectral pattern proved that the mass was a pseudoaneurysm, not a previously misdiagnosed venous thrombosis.

Cardiac ischemia-reperfusion can cause severe damage to cardiomyocytes. Previous studies have revealed that TGF-β can alleviate ischemia-reperfusion injury in cardiomyocytes by inducing the expression of long non-coding RNA (lncRNA) activated by TGF-β (ATB). However, M2 macrophages can secrete a large amount of TGF-β. However, whether M2 macrophages alleviate the ischemia-reperfusion-induced injury of cardiomyocytes by secreting TGF-β is unclear. In the present study, macrophages and cardiomyocytes were cultured under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions to simulate ischemia-reperfusion injury. M2-type macrophage markers (IL-10, Arginase-1 and IL-13) were validated using reverse transcription-quantitative PCR and western blotting. Subsequently, the culture medium of M2-type macrophages was collected for the treatment of cardiomyocytes, which were cultured under OGD/R conditions. The levels of inflammatory factors and oxidase enzymes were detected with ELISA. The apoptotic rates of cardiomyocytes were detected by flow cytometry. The expression of cell apoptosis-related proteins and the phosphorylation levels of NF-κB were analyzed by western blotting. The expression levels of specific inflammatory cytokines and the levels of malondialdehyde and lactate dehydrogenase were suppressed in cardiomyocytes following treatment with culture medium derived from M2-type macrophages, which were cultured under OGD/R conditions. Furthermore, OGD/R-induced apoptosis of cardiomyocytes was also relieved following treatment of the cells with macrophage medium. It was found that M2-type macrophages could secrete TGF-β and that the culture medium of M2-type macrophages could activate the expression of lncRNA ATB in cardiomyocytes. TGF-β secreted by M2 macrophages relieved the inflammatory response, oxidative stress and apoptosis of cardiomyocytes by inducing the expression of lncRNA ATB.

A calculation method based on a combination of ∆ g parallelism rule, good matching site (GMS) analysis, CSL/DSCL (coincidence site lattice/displacement shift complete lattice) and the O-lattice theory has been applied to interpret the observation of the habit plane (HP) of the δ precipitates and the linear defects in the HP in an Inconel 718 superalloy. The small scattering in the HP orientation around an ideal rational plane is interpreted by the existence of a mixture of two types of steps with different heights and inclinations. These steps play a significant role to enhance the degree of matching in the HP. They are associated with secondary dislocations, with Burgers vectors of \(1/6\left[ {1\;1\;\bar{2}} \right]_{\gamma } / 1/3[0\;0\;1]_{\delta }\), and with a direction parallel to a near-invariant line along \([1\;\bar{1}\;0]_{\gamma }\). The spacing of the secondary dislocations projected on the terrace plane is around 6.3 nm. The calculated dislocation structure is in good agreement with the observation.

A new orientation relationship (OR) is found between Widmanstatten cementite precipitates and the austenite matrix in a 1.3C-14Mn steel. The associated habit plane (HP) and the dislocations in the ...

We study the interactions between a cationic polypeptide chain with tunable hydrophobicity and a fluid phosphatidyl-choline lipid monolayer composed of neutral, tetravalent phosphatidylinositol 4, 5-bisphosphate and univalent phosphatidylserine acidic lipids at various ionic concentrations of the salt solution, using a simple coarse-grained Monte Carlo model. Our work illustrates that the enhancement in the polypeptide hydrophobicity strengthens the short-range attractions between monomers, which elevates the electrostatic energy gain of the polypeptide/membrane complexity, but enlarges the conformational entropy loss of the shrunken polypeptide and demixing entropy loss of the segregated acidic lipids. These energy-entropy competitions result in qualitatively different dependences of anchoring/dissociation transition critical ionic concentration on hydrophobic monomer-monomer energy parameter e h for polypeptides with short and long chain lengths. In the anchoring region, we show that changing the polypeptide hydrophobicity leads to diverse chain conformations at various ionic concentrations for polypeptides with both short and long chain lengths. Furthermore, we illustrate the non-trivial feature of the reorganization of the acidic lipids underneath the anchored polypeptides. Our work demonstrates that the chain conformations of the anchored polypeptides with different hydrophobicities can be a key factor influencing the amounts and concentration gradients of the segregated acidic lipids. These findings suggest that polypeptide hydrophobicity provides an efficient molecular factor for tailoring the anchoring/association transition and interfacial structures of the polypeptide/membrane complexities, thereby offering insight into the innovation of new biotechnologies based on the functional switch of the anchored biopolymers and the regulation of messenger lipids.

We investigate the thermodynamic and dynamic properties of a model unentangled glass-forming polymer melt over a wide range of pressures (P) and temperatures (T) using molecular dynamics simulation. We show that the T dependence of the reduced thermal expansion coefficient and isothermal compressibility becomes weaker for higher P. Based on the generalized entropy theory, these trends suggest that the isobaric fragility of glass formation decreases with increasing P, consistent with our analysis from the structural relaxation time (τα). Moreover, we confirm previous findings that the onset and end of the glass formation process in our model can be estimated solely based on the static structure factor. We then provide a detailed analysis for the T and P dependence of τα as well as other quantities characterizing the dynamic heterogeneity of glass-forming liquids. In particular, we discuss how T and P influence the average extent L of the stringlike cooperative motion of monomers in our model polymer melt, ...

We provide a computational test of the energy renormalization method to coarse-grain polymers with different segmental structures., Multiscale coarse-grained (CG) modeling of soft materials, such as polymers, is currently an art form because CG models normally have significantly altered dynamics and thermodynamic properties compared to their atomistic counterparts. We address this problem by exploiting concepts derived from the generalized entropy theory (GET), emphasizing the central role of configurational entropy sc in the dynamics of complex fluids. Our energy renormalization (ER) method involves varying the cohesive interaction strength in the CG models in such a way that dynamic properties related to sc are preserved. We test this ER method by applying it to coarse-graining polymer melts (i.e., polybutadiene, polystyrene, and polycarbonate), representing polymer materials having a relatively low, intermediate, and high degree of glass “fragility”. We find that the ER method allows the dynamics of the atomistic polymer models to be faithfully described to a good approximation by CG models over a wide temperature range.

Epithelial‑to‑mesenchymal transition (EMT) is a major process involved in tumor progression and metastasis. Melatonin is secreted by the pineal gland and has been documented as a potential therapeutic agent for multiple tumors. However, the effects of melatonin on EMT during osteosarcoma (OA) development remain undefined. The present study explored the biological functions and effects of melatonin on EMT induced by transforming growth factor β1 (TGF‑β1) and its underlying mechanisms in MG‑63 cells. Using western‑blotting and immunofluorescence, it was found that the switch in E‑cadherin/N‑cadherin and vimentin expression was induced by TGF‑β1, which was reversed by melatonin through the suppression of Snail and matrix metalloproteinase 9 (MMP‑9), through hypoxia‑inducible factor 1α (HIF‑1α) inhibition. These findings demonstrated that the anticancer effects of melatonin against OA MG‑63 cells is through the suppression of EMT via HIF‑1α/Snail/MMP‑9 signaling.

We develop a coarse-grained Monte Carlo model for the anchoring of cationic polymers onto a phosphatidyl-choline (PC) lipid monolayer, doped with univalent phosphatidylserine (PS) and tetravalent phosphatidylinositol 4, 5-bisphosphate (PIP2) anionic lipids. Using this model, we extensively explore the effects of important factors on the structural alterations of the polymers/monolayer complex, including the polymer concentration, the polymer ionization fraction and the ionic concentration of the salt solution. We find the substantial disparity in the scaling of the anchoring/dissociation transition for polymers/monolayer complex and polyelectrolyte/surface system, which demonstrates that the mobile anionic monolayer exerts stronger attraction on cationic polymers than uniformly charged surface, thereby illustrating the significant predominance of PIP2 lipids in the anchoring procedure. In the polymer anchoring regime, increasing the polymer ionization fraction drastically strengthens the attractions between polymers and the monolayer at low polymer concentrations, which in turn results in the transformation of individual polymer chains from a brush-like structure to a pancake-like structure and leads to the enhancement of PIP2 sequestration. Elevating the polymer concentration strengthens the competition of the anchoring between individual polymers, and the fraction of anchored polymers can even saturate at sufficiently high polymer concentrations. At high polymer concentrations, this competition forces both weakly and strongly charged polymers to anchor onto the membrane in the brush-like conformation, thereby sequestering smaller PIP2 clusters. The PS lipids cluster around the polymer/PIP2 complexes when the amount of tetravalent PIP2 lipids is insufficient to neutralize the anchored cationic polymers. We also observe that the monolayer can be overcharged due to the anchoring of polymers at high polymer concentrations. Our work thus approaches an improved understanding of the anchoring processes from a fundamental perspective based on the estimates of the stability and the structural variations of the polymers/monolayer complex with important molecular factors.

Monomer chemical structure and architecture represent the most important characteristics of polymers that affect basic molecular parameters (such as the microscopic cohesive energy parameter ϵ and chain persistence length) and that correspondingly govern the bulk physical properties of polymer materials. Here, we focus on elucidating how the microscopic parameter ϵ influences the bulk thermodynamic properties of polymer melts by using molecular dynamics simulations for a standard coarse-grained bead–spring model of unentangled polymer melts under both constant volume and constant pressure conditions. Basic dimensionless thermodynamic properties, such as the cohesive energy density, thermal expansion coefficient, isothermal compressibility, and surface tension, are found to be universal functions of the temperature scaled by ϵ, and thermodynamic signatures for the onset and end of glass formation are identified based on observable features from the static structure factor. We also find that general trends ...

The wide range of chemical compositions exhibited by polymers enables the fabrication of materials having highly tunable cohesive energy strength ϵ, and many of the properties that make polymers so useful as structural and responsive materials in both manufacturing and living systems derive from the variability of this basic property. The design and characterization of polymer materials then inevitably leads to a consideration of how ϵ impacts the thermodynamic and relaxation properties of polymer liquids. Our prior paper uses molecular dynamics simulations of a model coarse-grained polymer melt to systematically investigate the dependence of commonly measured thermodynamic properties on ϵ, while the present work focuses on the relaxation dynamics of the same molecular model. After demonstrating, as expected, that ϵ greatly influences the segmental relaxation time, we obtain a universal reduction of all our data for relaxation in terms of an activated transport model in which the activation free energy is...

Aiming at the management issue of mass sensory data from the manufacturing resources in cloud manufacturing, a management method for mass sensory data based on Hadoop is proposed. Firstly, characteristics of sensory data in cloud manufacturing are analyzed, meanings and advantages of Internet of Things and cloud computing are elaborated. Then the structure of the cloud manufacturing service platform is proposed based on Hadoop, the information model of manufacturing resources in cloud manufacturing is defined, and the data cloud in the cloud manufacturing service platform is designed. The distributed storage of mass sensory data is implemented and a universal distributed computing model of mass sensory data is established based on the characteristics of Hadoop Distributed File System (HDFS).

Based on non-equilibrium molecular dynamics simulations of entangled polymer melts, a recent Letter [Phys. Rev. Lett. $\textbf{121}$, 047801 (2018), arXiv:1806.09509] claims that the rising extensional stress is quantitatively consistent with the decreasing entropy of chains at the equilibrium entanglement length. We point out that exactly the opposite is true: the intrachain entropic stress arising from individual entanglement strands generally does not agree with the total "macroscopic" stress. The conclusion of the Letter is based on an incomplete and questionable analysis of a limited range of the simulation trajectory. The opposite conclusion should have been drawn from their data, had they examined the full simulation trajectory in a proper way.

Drawing an analogy to the paradigm of quasi-elastic neutron scattering, we present a general approach for quantitatively investigating the spatiotemporal dependence of structural anisotropy relaxation in deformed polymers by using small-angle neutron scattering. Experiments and non-equilibrium molecular dynamics simulations on polymer melts over a wide range of molecular weights reveal that their conformational relaxation at relatively high momentum transfer $Q$ and short time can be described by a simple scaling law, with the relaxation rate proportional to $Q$. This peculiar scaling behavior, which cannot be derived from the classical Rouse and tube models, is indicative of a surprisingly weak direct influence of entanglement on the microscopic mechanism of single-chain anisotropy relaxation.

We apply monte carlo simulation to explore the adsorption of a positively charged polyelectrolyte on a lipid monolayer membrane, composed of electronically neutral, monovalent anionic and mulvitalent anionic phospholipids. we systematically assess the influence of various factors, including the intrinsic rigidity of the polyelectrolyte chain, the bead charge density of the polyelectrolyte, and the ionic strength of the saline solution, on the interfacial structural properties of the polyelectrolyte/monolayer complex. the enhancement of the polyelectrolyte chain intrinsic rigidity reduces the polyelectrolyte conformational entropy loss and the energy gains in electrostatic interaction, but elevates the segregated anionic lipid demixing entropy loss. this energy-entropy competition results in a nonmonotonic dependence of the polyelectrolyte/monolayer association strength on the degree of chain rigidity. the semiflexible polyelectrolyte, i.e., the one with an intermediate degree of chain rigidity, is shown to associate onto the ternary membane below a higher critical ionic concentration. in this ionic concentration regime, the semiflexible polyelectrolyte binds onto the monolayer more firmly than the pancake-like flexible one and exhibits a stretched conformation. when the chain is very rigid, the polyelectrolyte with bead charge density z(b) = +1 exhibits a larger tail and tends to dissociate from the membrane, whereas the one with z(b) = +2 can still bind onto the membrane in a bridge-like conformation. our results imply that chain intrinsic rigidity serves as an efficient molecular factor for tailoring the adsorption/desorption transition and interfacial structure of the polyelectrolyte/monolayer complex.

Chemical structure has been long recognized to greatly influence polymer glass formation, but a general molecular theory that predicts how chemical structure determines the properties of glass-forming polymers has been slow to develop. While the generalized entropy theory (GET) explains the influence of various molecular details on polymer glass formation, the application of the GET has heretofore been limited to the use of the simplest polymer model in which all united atom groups within the monomers of a species interact with a common monomer averaged van der Waals energy. However, energetic heterogeneities are ubiquitous within the monomers of real polymers, and their implications for polymer glass formation remain to be investigated theoretically. This paper uses an extension of the GET to explore the influence of energetic heterogeneities within monomers upon the nature of polymer glass formation. The present paper focuses on establishing general trends for the variation of characteristic properties of glass formation, such as the isobaric fragility parameter $m_P$ and the glass transition temperature $T_g$, with molecular details, such as the specific interactions and chain stiffness. Our computations confirm that the previously used model with monomer averaged interactions correctly captures general trends in the variation of $m_P$ and $T_g$ with various molecular parameters. More importantly, adjustment of the energetic heterogeneities within monomers alone are shown to provide an efficient mechanism for tailoring the properties of glass-forming polymers. The variations of polymer properties along iso-fragility and iso-$T_g$ lines are illustrated as important design tools for exhibiting the combined influence of specific interactions and chain stiffness., Comment: 13 pages, 14 figures, to be published in Macromolecules. arXiv admin note: text overlap with arXiv:1409.6781