Soft Rubber rapid prototype, Hardness is generally between shore A 30~90 degrees, because soft rubber plastic prototype has flexibility, it is widely used in the rapid prototype industry. The processing method of soft plastic rapid prototype is relatively single, and it can only be processed by vacuum Casting - that is use 3D printing or CNC processing to do a prototype, and then use vacuum casting /silicone mold to copy the prototype, generally a prototype can be copied 15~20 time.
In the general plastic industry, PP, PE and other light gravity, material surface hardness is relatively low plastic known as soft glue. And PS, ABS, AS, hard PVC and other plastics can be called hard glue.
Silicone products are silicon - oxygen (Si-O) key chain structure, C-C bond energy of 82.6 kilocalories/gram molecule, Si-O bond energy in silicone is 121 kilocalories/gram molecule, so the thermal stability of silicone products is high, high temperature (or radiation) molecular chemical bonds do not break, do not decompose. Silicone not only can withstand high temperature, but also low temperature, can be used in a wide temperature range. Both chemical and physical mechanical properties change very little with temperature.
The main chain of organosilicon products is -Si-O-, no double bond exists, so it is not easy to be decomposed by ULTRAVIOLET light and ozone. Silicone has better thermal stability and radiation resistance and weather resistance than other polymer materials. The service life of organic silicon in the natural environment can reach several decades.
Silicone products have good electrical insulation performance, its dielectric loss, voltage resistance, arc resistance, corona resistance, volume resistivity and surface resistivity are among the best insulating materials, and their electrical performance is very little affected by temperature and frequency. Therefore, they are a stable electrical insulation material, which is widely used in electronic and electrical industries. In addition to excellent heat resistance, silicone also has excellent water repellency, which is the guarantee of high reliability for the use of electrical equipment under wet conditions.
Polysiloxanes are among the least active compounds known. They are very resistant to biological aging, have no rejection reaction with animal body, and have good anticoagulant ability.
The main chain of silicone is very supple, the intermolecular force is much weaker than hydrocarbons, therefore, than the same molecular weight hydrocarbon viscosity is low, weak surface tension, surface energy is small, film forming ability is strong. This low surface tension and low surface energy is the main reason for its many applications: hydrophobic, defoaming, foam stability, anti-stick, lubrication, glazing and other excellent properties.
Soft rubber rapid prototype is mainly processed by the way of silicone compound mold, its advantages are fast time, less cost, good operation, no deformation, no shrinkage, easy to dismantle the mold, the mold surface is smooth, the simulation effect is good, the probability of processing failure is small. 10-20 pieces of the same product can be copied by using a silica gel mold. Generally, a set of silica gel mold can only be done about 10-20 times and can not be used. Reuse can produce deformation and large size error. Soft rubber hand model because of these excellent properties, so its application is very wide, Soft rubber hand model production steps can be divided into three steps, before making silica gel mold, first of all to make a prototype, the prototype can use the more common ABS material, can be made by CNC processing or 3D printing; After the original is ready, began to make silica gel mold, after curing, the silica gel mold is cut, take out the prototype, at this time the silica gel mold is ready; The liquid material is injected into the silica gel mold and dried. The service life of the silica gel mold is about 10-20 times. In the raid prototype industry, as long as the soft adhesive material is PU 8400.