POLYMER BLENDS

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					         POLYMER BLENDS
Enhancing The Educational Experience
      Through Self-Discovery and
           Experimentation


   MY RET EXPERIENCE




       LisaSophia Dovas
       WHAT ARE POLYMERS?
                          molecule



               molecule                  molecule
                          molecule




                   molecule          molecule




When tiny molecules (MONOMERS) are strung in long repeated
                 chains, they form polymers.
WHY SHOULD WE CARE?
  POLYMERS ARE EVERYWHERE!!

** Our body is made of them (DNA).




** They are in the proteins and starches we eat.



** They are in the wheels on our skateboards
   and in-line skates.



** They are in the tires on our bikes
   and cars.
Bonding for blending the possibilities
        are never ending!!!
 Sometimes we want a material that has the
  same properties of one polymer, and some
  of the properties of another.
 Instead of synthesizing a brand new
  polymer we try to mix two polymers together
  to form a blend with all the qualities that we
  want.
       WHY ARE WE BLENDING?
► To make a hydro-gel for medical uses.
► To simulate body tissues.
► To obtain certain properties:
   Durable, elastic, smooth
   Form memory
   Biologically “friendly”
        WHAT ARE “WE” BLENDING?


   25% PNIPAam with 5% PVA

   PNIPAam is Poly-N-isopropyl acrylamide
       A “smart” polymer, that changes its property according to its environment.

       Poly N-isopropyl acrylamide (PNIPAAm) exhibits lower critical solution temperature (LCST) and is known to undergo phase
        transition when the temperature is raised from room temperature to about 32*C.



   PVA is Poly Vinyl Alcohol
       A water soluble polymer, non-toxic and free of danger, that can be used in the production of various things such as: paper, clothes, glues, paints,
        pharmaceutical products, building materials, ceramics, etc.



   Ratios of:
                      1:1                   25% PNIPAam : 5% PVA
                      2:1                   25% PNIPAam : 5% PVA
                      1:2                   25% PNIPAam : 5% PVA
            O     O        O       O        O
                                                   PVA
CH(CH3)2    H     H        H       H        H
                                                Interchain
                                                Hydrogen
 N     C O                 O                    Bonding
 H                             C
                                       NH          PNIPAAm
       CH             CH
                                       CH(CH3)2
 CH2        CH2            CH2

Polymer chemistry of PVA/PNIPAAm hydrogel depicting
                 hydrogen bonding
         SO HOW DO WE DO IT?
   Make 25% Polymer
    (PNIPAam) solution.
       IE Weigh out 3 grams PNP and add 9 ml of
        DI (chilled).

   Make 5% PVA solution.
       IE Similar process 5 g PVA to 95 ml DI,
        stir for two hours and place in oven
        overnight.
   Ratios of PVA to PNPAam
       Weigh out given amount of PNP then use
        ratios to determine the amount of PVA for
        Example:
       3g PVA : 3g PNP for 1:1
       3g PVA : 6g PNP for 1:2
       6g PVA : 3g PNP for 2:1
       WHAT DID WE DO WITH
             THEM?
• Split each ratio into two
  equal parts.
   – One half, crashed out
     (became solid).
   – Other half, air dried.
• Samples:
   – Crushed vs crashed
   – Analyzed in DSC and
     FTIR
SPECIAL THANK YOU!!!




Dr. Tony Lowman   Dr. Michele Marcolongo   Garland Fussell




                                Joe                     Jenn

				
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