Helen and Ian have a set of cutlery with acrylic handles in which are captured bubbles. I find this fascinating but can think of no way that the effect can be achieved given that no bubbles are near the surface of the acrylic. Does anyone know the answer?
I think that this probably isn't as difficult as it sounds. I remember making acrylic during A-Level chemistry and letting it set in a testtube (which gives a similar shape to the handles).
ReplyDeleteOnce my small amount of acrylic had set it did have bubbles in it, and like these they were all towards the middle.
I'm assuming that as it is quite thick the air bubbles take quite a while to work towards the edge and hence can be easily trapped inside the acrylic as it dries. However, if they get close to the edge the large polymer chains in the acrylic will probably slide apart letting the bubble out and quickly filling the resulting hole.
I assume in a commercial process they will actually pump air into the mould as the acrylic is setting. Knowing the setting time means they will know just how much air to pump in to get the desired effect.
the wonders of a proper education!
ReplyDeleteWhy are polymers in chains - do they have a habit of escaping?
ReplyDelete