The Glass Transition (a free volume view)
There is movement.
Thus: The world is not full.
There is empty space.
The nothing, the void, does exist.
Thus: The world consists of the existing,
the hard and full, and the void:
Of ‘atoms and the void’
-Democritus ca. 400 BC (trans. Karl Popper)
Research Areas
- Thermal and Mechanical Properties of Epoxies
- 相变和非均相聚合物材料热力学
- Chemical Kinetics
- Molecular Dynamics Simulations
- Density Functional Theory
- Glass Transition
Plain Language Summaries of Recent Research
用硬化剂二乙醇胺固化DGEBA环氧树脂的量热研究 (DEA). 固化涉及一系列复杂的反应(包括两性离子的形成, anionic chain growth, and termination). The tertiary amine formed after initial reaction 形成加合物的仲胺的作用是打开环氧环形成 zwitterion which then propagates in chain growth. The hydroxyls accelerate the reaction. 目前,我们正通过研究DGEBA反应来分离贡献 dibutylamine and octanol.
Recent Publications
双酚A环氧树脂二缩水甘油酯醚与二乙醇胺固化的反应 Dependency on temperature and extent of reaction, McCoy, Ancipink, Maestas, Draelos, Devries, Kropka, thermochemica Acta(已提交2018)
研究了低导热环氧树脂的绝缘对分辨率的影响 用差示扫描量热法测定聚合过程中的反应热, Arechederra, Draelos, Ancipink, McCoy, Kropka, Thermochimica Acta 656, 144 (2017)
双酚A环氧树脂二缩水甘油酯醚与二乙醇胺固化机理研究, McCoy, Ancipink, Clarkson, Kropka, Celina, Giron, Hailesilassie, Fredj, Polymer 105, 243 (2016)
Recent Presentations
羟基浓度对双酚二缩水甘油醚固化动力学的影响 A (DGEBA) epoxy in the presence of a tertiary amine, McCoy, M. House, E. House, S. Comeau, C. House, Kropka, Poster, American Physical Society, Los Angeles, CA (2018)
羟基迁移率对双酚二缩水甘油醚固化动力学的影响 A (DGEBA) epoxy in the presence of a tertiary amine, D. Devries, M. House, E. House, S. Comeau, C. House, McCoy, Kropka,海报,美国物理学会,洛杉矶,加州(2018)
羟基对环氧树脂叔胺固化的影响, M. House, E. House, S. Comeau, C. House, McCoy, Kropka,海报,AiChe年会,明尼阿波利斯,MN (2017)
叔胺活化反应在DGEBA环氧硬化中的复合固化动力学 with Diethanolamine, Ancipink, McCoy, Clarkson, Kropka, Celina, Giron, Hailesilassie, Fredj, Poster, American Physical Society, New Orleans, LA (2017)
环氧树脂硬化过程中羟基-环氧化物反应的复合固化动力学 Diethanolamine, Ancipink, McCoy, Kropka, Celina, Poster,美国物理学会,马里兰州巴尔的摩(2016)
Thesis
叔胺固化环氧树脂固化动力学研究 Diethanolamine – Ancipink (2017)
玻璃的热性能和机械性能随着时间的推移而变化,因为它们在温度下“老化” below their glass transition. Two epoxies have been studied. DGEBA cured with diethanolamine (DEA) and DGEBA cured with a polyamine Jeffamine T-403. Use is made of simple theories of aging (e.g., KAHR and Eyring Models) to understand the aging process. Particularly 有趣的是压应力对老化的影响,两者都很小, sub-yield stresses and large, post-yield stresses are studied.
Recent Publications
二乙醇胺固化二缩水甘油醚的热力学性能演变 of Bisphenol-A (DGEBA) Epoxy, Arechederra, McCoy, Kropka, Polymer (To be Submitted - Draft)
胺固化DGEBA环氧树脂的焓恢复及其与剪切响应的关系, Clarkson, McCoy, Kropka, Polymer 94, 19 (2016)
Recent Presentations
机械回春后环氧玻璃老化的量热特征, Comeau, M. House, E. House, Hoo, McCoy, Kropka,海报,美国物理学会,洛杉矶,加州(2018)
环氧树脂828DEA结构松弛过程中屈服应力的演化, Arechederra, McCoy, Kropka,海报,美国物理学会,巴尔的摩,马里兰州(2016)
828dgeba环氧树脂长时间弛豫特性研究, Hoo, Reprogle, Wisler, Arechederra, McCoy, Kropka, Long, Poster,美国物理学会,马里兰州巴尔的摩(2016)
Thesis
828/DEA环氧树脂结构弛豫过程中力学性能的演变 Thermoset, Arechederra (2017)
聚醚胺固化DGEBA环氧树脂物理老化的影响 Wilson (2018)
一个长期存在的问题是薄膜的厚度如何影响玻璃 properties (e.g., glass transition temperature and relaxation behavior). Two of us (Curro和McCoy)提出了基于密度泛函理论的how和Tg理论 varies with film thickness. In collaboration with former student, Stevenson, we are exploring this connection with Molecular Dynamics Simulations. Current work is focusing on relaxation times.
Recent Publication
薄膜的玻璃化转变温度:珠状弹簧的分子动力学研究 model, Stevenson, Curro, McCoy, Journal of Chemical Physics 146, 203322 (2017).
Students Past and Present
Stephan Comeau (Current)
Jonathan R. Brown
简单模拟聚合物的线性和非线性动态热容(2012)
Joanne L. Budzien
用标量研究链式分子玻璃化转变的计算机模拟
Metric Approach (2004)
Shyamal K. Nath
非均相聚合物体系的结构和热力学:表面,共混物
and Diblocks (1996)
Giovanni Gabaldon (Current)
Brandon McReynolds (Current)
Noah White
Effect of aging on the syntactic foam DGEBA/DEA/GMB (2022)
Kelsey Wilson
Physical aging In a polyether-amine cured DGEBA epoxy (2018)
Gabriel Arechederra
828/DEA环氧热固性材料热力学性能的演变(2017)
Windy Ancipink
叔胺活化环氧树脂固化动力学研究
diethanolamine (2017)
Caitlyn Clarkson
Structural Relaxation of a DGEBA Epoxy 828/T403 (2015)
Sara Waters
离子载流子扩散率和迁移率的分子动力学模拟
in Model Poly(ethylene-co-acrylic acid) Monomers (2014)
Jonathan Brown
Dynamic Heat Capacity of the East Ising Model (2009)
Taylor Dotson
简单聚合物分子动力学模拟中的弛豫行为(2008)
Julieanne V. Heffernan
Molecular Flexibility Effects Upon Liquid Dynamics (2007)
Kristy Visconti
玻璃纤维增强材料的三维热力学特性
Polymer-Matrix Composites (2007)
Yuan Ye
栓系聚合物链在不同溶剂中的结构:密度泛函理论
Study (2002)
Steven Deal
未固化环氧树脂/填料复合材料的流动特性(2002)
Morgan T. Pileggi
非理想流体和流体混合物的溶剂化热力学研究(2001)
Dana R. Rottach
小分子在聚合物中的扩散:分子动力学研究(1999)
Justin B. Hooper
硬壁附近切线硬球链的相互作用:密度泛函
Theory Approach (1999)
Joanne L. Budzien
橡胶聚合物中简单气体溶解度的预测(1998)
Patrick A. Tillman
吸引相互作用对模型聚合物液体结构的影响(1997)
Timothy (Dash) Weeks
断裂性能与环氧树脂网络反应程度的关系(1997)
Sudeepto Sen
硬壁附近旋转异构烷烃熔体的结构(1994)
Craig S. Stevenson
二元均聚物共混物的分子动力学模拟及与
the Polymer Reference Interaction Site Model (1994)
Meltem Zorlu
再生高密度聚乙烯的热特性(1994)
许多大学生都是小组成员——这个名单可能不完整
Taylor Lee
Brandon McReynolds
Noah White
Adrianna Nieto
Catherine House
Catherine Groves
Margaret House
Kelsey Wilson
Sam Burleigh
Eleanor House
Katheryn Husmann
Brian Wisler
Riley Reprogle
Victoria J. Aston
Francisco Avila
Robert J. Baca
Gwendolyn Bahun
Ethan Buchner
Andrea Buckel
Partick Burton
K. Thomas Dotson
Shannon Ferrel
Annie Hohmann
Phillip Jenks
Ganlu "Lulu" Liu
Tyler Payton
Salomon Mateas
Daniel McCoy
Katheryn Mireles
Robin Montoya
Matthew Rush
Timothy Schutt
Jason Sharkey
Laura Stanley
Meredith Schuh
Melody A. Teixeira
Devon Turner
Jedediah (J.D.) Tratechaud