Observation of Glass Transition Temperatures in Polymeric Thin Films by Wafer Curvature Measurements

ABSTRACTWafer bending measurements have been used to study the glass transition temperature, Tg, of thin coatings of polystyrene and polycarbonate on Si wafers. The observed values of Tg agree with DSC and TMA measurements on bulk samples. The evolution of the substrate curvature has been used to examine the behavior of Tg in thin epoxy films and coatings derived from divinylsiloxane bisbenzocyclobutene, mixed stereo and positional isomers of 1, 3-bis(2-bicyclo[4.2.0]octa-1, 3, 5-trien-3-ylethenyl)-1, 1, 3, 3-tetramethyl disitoxane (CAS 117732–87–3). The dependence of the Tg of the epoxide coatings is studied as a function of the cross-linking. The evolution of the Tg in the benzocyclobutene coating is found to be a monotonie function of the level of conversion of the polymer network.

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The Effects of Cross-Linking and Strain on the Glass Transition Temperature of a Polymer Network

Rubber Chemistry and Technology ◽

10.5254/1.3535073 ◽

1980 ◽

Vol 53 (4) ◽

pp. 982-987 ◽

Cited By ~ 7

Author(s):

M. A. Sharaf ◽

J. E. Mark

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Polymer Network ◽

Thermal Shrinkage ◽

Cross Linking ◽

Scanning Calorimetry ◽

Increase With Increase ◽

Strain Induced Crystallization ◽

Induced Crystallization

Abstract The glass transition temperature Tg of an elastomer is of great importance with regard to its utilization since at this temperature and below, the material can no longer exhibit rubberlike behavior. In the present study, networks were prepared from atactic poly(vinyl acetate) and poly(isobutyl methacrylate), both types of networks being inherently non-crystallizable and therefore immune from complications associated with strain-induced crystallization. The values of Tg were obtained by dilatometry, differential scanning Calorimetry, the measurement of viscoelastic losses, and irreversible thermal shrinkage. For both types of networks, Tg was found to increase with increase in degree of crosslinking and with increase in elongation. These results suggest that the most important effect of crosslinking and network elongation is a decrease in the mobility or entropy of the network chains.

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High Glass Transition Temperature Fluoropolymers for Hydrophobic Surface Coatings via RAFT Copolymerization

Australian Journal of Chemistry ◽

10.1071/ch15787 ◽

2016 ◽

Vol 69 (7) ◽

pp. 725 ◽

Cited By ~ 3

Author(s):

Molly Rowe ◽

Guo Hui Teo ◽

James Horne ◽

Omar Al-Khayat ◽

Chiara Neto ◽

...

Keyword(s):

Thin Films ◽

Contact Angle ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Surface Coatings ◽

Transition Temperatures ◽

High Glass Transition Temperature ◽

Glass Transition Temperatures ◽

Hydrophobic Polymers

The preparation of polymer thin films or surface coatings that display a static water contact angle >95° often requires hierarchical roughness features or surface functionalization steps. In addition, inherently hydrophobic polymers such as fluoropolymers often possess low glass transition temperatures, reducing their application where thermal stability is required. Herein, the first reported synthesis of 2,3,4,5,6-pentafluorostyrene (PFS) and N-phenylmaleimide (NMI) via reversible addition–fragmentation chain-transfer (RAFT)-mediated free radical polymerization is presented, with a view towards the preparation of inherently hydrophobic polymers with a high glass transition temperature. A suite of copolymers were prepared and characterized, and owing to the inherent rigidity of the maleimide group in the polymer backbone and π–π interactions between adjacent PFS and NMI groups, very high glass transition temperatures were achieved (up to 180°C). The copolymerization of N-pentafluorophenylmaleimide was also performed, also resulting in extremely high glass transition temperature copolymers; however, these polymers did not exhibit characteristics of being under RAFT control. Thin films of PFS-NMI copolymers exhibited a static contact angle ~100°, essentially independent of the amount of NMI incorporated into the polymer.

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Azobenzene molecular glasses with tuned glass transition temperatures: from optimal light-induced motion to self-erasable gratings

Journal of Materials Chemistry C ◽

10.1039/d0tc00393j ◽

2020 ◽

Vol 8 (18) ◽

pp. 6203-6213

Author(s):

Austin Diggins ◽

Eoin Dawson ◽

Mahnaz Kamaliardakani ◽

Christian Pellerin ◽

Ribal Georges Sabat ◽

...

Keyword(s):

Thin Films ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Surface Relief ◽

Transition Temperatures ◽

Molecular Glasses ◽

Glass Transition Temperatures ◽

Induced Motion ◽

Surface Relief Gratings

The rate of photomechanical formation of surface relief gratings (SRG) in thin films of azobenzene materials depends on their glass transition temperature (Tg), with self-erasable gratings being formed with materials with sub-ambient Tg.

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Impact of Surface-Modified Nanoparticles on Glass Transition Temperature and Elastic Modulus of Polymer Thin Films

Macromolecules ◽

10.1021/ma071332s ◽

2007 ◽

Vol 40 (22) ◽

pp. 7755-7757 ◽

Cited By ~ 39

Author(s):

Jong-Young Lee ◽

Kristin E. Su ◽

Edwin P. Chan ◽

Qingling Zhang ◽

Todd Emrick ◽

...

Keyword(s):

Thin Films ◽

Glass Transition ◽

Elastic Modulus ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Polymer Thin Films ◽

Surface Modified ◽

Surface Modified Nanoparticles

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Variations in the glass transition temperature of polyester with special architectures confined in thin films

Polymer ◽

10.1016/j.polymer.2009.11.032 ◽

2010 ◽

Vol 51 (1) ◽

pp. 129-135 ◽

Cited By ~ 23

Author(s):

M. Erber ◽

A. Khalyavina ◽

K.-J. Eichhorn ◽

B.I. Voit

Keyword(s):

Thin Films ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature

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A Copolymerization Modified Acrylate Resin and its Polyhedral Oligomeric Silsesquioxane Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.887-888.97 ◽

2014 ◽

Vol 887-888 ◽

pp. 97-100

Author(s):

Xiao Lan Hu ◽

Xi Lan ◽

Teng Fei Lu ◽

Hong Shan Yang ◽

Ying Lai Yang

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Polyhedral Oligomeric Silsesquioxane ◽

Glass Transition Temperatures ◽

Acrylate Copolymer ◽

Amino Resin ◽

Acrylate Resin ◽

Oligomeric Silsesquioxane ◽

Physical Blending ◽

Better Than

An acrylate resin copolymerized with epoxy and amino resin was prepared in this paper, and its polyhedral oligomeric silsesquioxane (POSS) modified nanocomposites were fabricated via physical blending. Results showed that glass transition temperature of the acrylate copolymer was about 7.9 oC via DSC. Dispersion of nanocomposites with aminopropyllsobutyl POSS is better than those with Octalsobutyl POSS. Moreover, glass transition temperatures of the nanocomposites with POSS are close to the acrylate copolymer matrix.

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Silk Polymer Coating with Low Dielectric Constant and High Thermal Stability for Ulsi Interlayer Dielectric

MRS Proceedings ◽

10.1557/proc-476-9 ◽

1997 ◽

Vol 476 ◽

Cited By ~ 46

Author(s):

P. H. Townsend ◽

S. J. Martin ◽

J. Godschalx ◽

D. R. Romer ◽

D. W. Smith ◽

...

Keyword(s):

Thin Film ◽

Dielectric Constant ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Integrated Circuits ◽

Room Temperature ◽

Polymer Network ◽

Flow Characteristics ◽

Interlayer Dielectric

AbstractA novel polymer has been developed for use as a thin film dielectric in the interconnect structure of high density integrated circuits. The coating is applied to the substrate as an oligomeric solution, SiLK*, using conventional spin coating equipment and produces highly uniform films after curing at 400 °C to 450 °C. The oligomeric solution, with a viscosity of ca. 30 cPs, is readily handled on standard thin film coating equipment. Polymerization does not require a catalyst. There is no water evolved during the polymerization. The resulting polymer network is an aromatic hydrocarbon with an isotropie structure and contains no fluorine.The properties of the cured films are designed to permit integration with current ILD processes. In particular, the rate of weight-loss during isothermal exposures at 450 °C is ca. 0.7 wt.%/hour. The dielectric constant of cured SiLK has been measured at 2.65. The refractive index in both the in-plane and out-of-plane directions is 1.63. The flow characteristics of SiLK lead to broad topographic planarization and permit the filling of gaps at least as narrow as 0.1 μm. The glass transition temperature for the fully cured film is greater than 490 °C. The coefficient of thermal expansivity is 66 ppm/°C below the glass transition temperature. The stress in fully cured films on Si wafers is ca. 60 MPa at room temperature. The fracture toughness measured on thin films is 0.62 MPa m ½. Thin coatings absorb less than 0.25 wt.% water when exposed to 80% relative humidity at room temperature.

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Organo-Soluble, Segmented Rigid-Rod Polyimides: Synthesis and Properties

MRS Proceedings ◽

10.1557/proc-227-3 ◽

1991 ◽

Vol 227 ◽

Cited By ~ 15

Author(s):

F. W. Harris ◽

S. L. C. Hsu ◽

C. J. Lee ◽

B. S. Lee ◽

F. Arnold ◽

...

Keyword(s):

Thin Films ◽

Thermal Expansion ◽

Glass Transition ◽

Oxidative Stability ◽

Organic Solvents ◽

Dielectric Constants ◽

Glass Transition Temperatures ◽

Thermal Expansion Coefficients ◽

Rigid Rod ◽

Expansion Coefficients

ABSTRACTSeveral segmented, rigid-rod polyimides have been prepared that are soluble in organic solvents in their fully imidized form. The polymers were prepared from commercial dianhydrides and 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl (TFMB). Their intrinsic viscosities ranged from 1.0 to 4.9 dL/g. Tough, colorless films could be cast from m-cresol solutions at 100°C. The polymers had glass transition temperatures (Tgs) above 275°C and displayed outstanding thermal and thermo-oxidative stability. Fibers were prepared from the 3,3′,4,4′-tetracarboxybiphenyl dianhydride (BPDA) based polymers that had moduli of 130 GPa and tensile strengths of 3.2 GPa. The thermal expansion coefficients and dielectric constants of thin films (20–25 μm) of the polymers were as low as −2.40×10−6 and 2.5, respectively.

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