soft pvc
soft pvc
(OP)
I am designing very flexible pvc tube around 55 durometer hardness, but the tubes stick to each other while extruding. How can I change the texture of the tube so that they don't get tacky or sticky while extruding. Also, is there any additive that makes soft clear pvc opaque?





RE: soft pvc
The way to stop the tubes sticking together is to extrude into a water bath and to keep the tubes seperated.
The question about making it opaque sounds to stupid to be contemplated, so I will presume you do not understand the terminology of colours.
I will presume by opaque you actually mean opalescent which is certainly not opaque.
Opalescent is the translucent white colours very often used in light diffusers. It allows a significant proportion of the light to pass through, but scatters it.
It is quite difficult to get a good consistent opal colour in polymers that are a lot clearer than PVC, but if you don't mind slightly yellow tint that varies I am sure it can be done. Processing conditions will also be critical as varying shear can influence the particle size and quality of dispersion of the pigments as well as varying the yellow tint of the PVC rein.
Regards
Pat
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RE: soft pvc
Do you have any favorite books or journals in plastics?
RE: soft pvc
You can even make a material that changes transparency reversibly with temperature (I've made such a material, it's called ThermoShift).
Chris DeArmitt PhD FRSC CChem
RE: soft pvc