1. Relative Influences Of Polarity and Crystallinity On Zero-Order Kinetic Release Through a Polymer Membrane
Adam Dormier, Abhishek Gami, Kelly Gao, Christopher
Jagoe, Robert Ju, Daniel Li, Joshua Lopez, Jae Woong
Noh, Madison Parry, Maurice Wong, Agustin Zavala
Dr. David Cincotta, Timothy Barnum

2. Controlled Release Kinetics
Release of a chemical at a zero or pseudo-zero order rate
Many applications
biological
agricultural
medical

3. 2010 Douglas et al.

4. Polymers and EVA Polymers - Macromolecules Polarity Crystallinity
EVA - copolymer

6. Diffusion Governed by Fick’s Law Factors that affect rate 𝐽=−𝐷 𝜕𝜇 𝜕𝑥
polarity
crystallinity
molecular size
molecular shape

7. Rationale
Increasing EVA % → increasing polarity and decreasing crystallinity
Work in opposition for nonpolar substances
Which affects diffusion more?

8. Hypothesis Crystallinity greater impact than polarity
Diffusion coefficients will rise with more vinyl acetate

9. History 2010 team created apparatus and achieved zero- order kinetics
Hypothesized polarity  affected rate
2010 Douglas et al.

10. Methods We used 2010 team’s methodology for experiment
Liquids in Petri dishes covered by EVA films
Petri dishes massed over time to calculate flux rates
NEEDS TO BE FIXED

11. Calculations Fick’s first law of diffusion
𝐽=−𝐷 𝜕𝜇 𝜕𝑥
𝐽=−𝐷 𝑉𝑃 𝑖 − 𝑉𝑃 𝑜 𝑇
Diffusion coefficient: accounts for factors that change diffusion rate
Surface area and thickness of the film
Vapor pressure of the substance
Calculated D using experimental factors

12. Nonpolar Results )

14. Polar Solutes
Direct correlation seen between polarity and diffusion rates
Increasing polar regions of membrane facilitates diffusion
Decreased crystallinity and increased polarity act in unison to increase diffusion

15. Polar Solutes Ra values show degree of solubility
(Ra)2 = 4(δd2-δd1)2 + (δp2-δp1)2 + (δh2-δh1)2
Ra values show degree of solubility
No strong correlation seen between solubility and diffusion
Solubility and polarity are not significant

16. Conclusion
A polymer membrane’s crystallinity has a greater impact than its polarity on
Nonpolar solutes
Polar solutes

17. Future Experiments
Effect of molecular mass and morphology on the diffusion coefficient
Diffusion with various solutes
Further testing on the effect of polarity
esters
ketones
aldehydes
Relationship between solubility parameters of solutes and EVA films

18. Acknowledgments Dr. David Cincotta, advisor Timothy Barnum, assistant
Dr. Adam Cassano & Dr. Steve Surace, co-directors
AT&T           
Roche Foundation           
Celgene
Novartis Pharmaceuticals Corp
Independent College Fund of NJ
Watson Pharmaceuticals-Actavis
Charles Edison Foundation
Randolph and Lesly Rogers Charitable Fund
NJGSS Alumnae and Parents of Alumnae
Laura (NJGSS ’86) and John Overdeck
Board of Overseer’s, New Jersey Governor’s Schools

19. Thank you ! Any questions?