When smaller monomers are linked together, they form larger polymers which are normally stronger and more durable. Dissolved in water, sodium borate acts as a binding agent when added to polyvinyl alcohol (PVA), cross-linking the polymers by reacting with the hydroxyl groups in PVA (Baker). When this cross-link occurs, it produces four molecules of water as a byproduct (Figure 1) (“Experiment 2”). Polyvinyl acetate (PVAc) is a rubbery polymer, capable of strong binding and flexibility (Dyslex). PVAc reacts with water, producing acetic acid and a hydroxyl group (Calder). The boric acid from sodium borate reacts with both the PVA hydroxyl groups, and those released from PVAc’s reaction with water (Calder). When combined together in the correct …show more content…
While the PVAc polymers did cross-link due to the borate ions interaction with the hydroxyl groups, the resulting material was very soft, malleable, and sticky (Table 1). When left untouched for an extended period of time, the ball lost shape and flattened. A small amount of liquid, presumably water as a product of the reaction, remained in the bottom of the beaker. When more PVAc was used than borate, the PVAc was stringy and did not clump together as well (Table 1). Borate, PVAc, and PVA: When borate was first added to PVA, it became thicker and viscous. Then, when the PVAc was mixed in, it clumped together just as with only borate. However, the resulting material appeared more rubbery and solid, and less sticky (Table 2). In trials four and six, no liquid was remaining at the bottom of the beakers. In trial seven, the PVAc did not clump together as well as in previous trials (Table2). Adding cornstarch to mixtures: Both trials involving cornstarch added directly to the mixture in the cup resulted in similar material. While the material appeared slightly more firm, there was overall not a noticeable difference between the mixtures without cornstarch added (Table