Home > Products > Chemicals > Rubber Materials

Definition of silicone rubber:

Silicone is an industry name, it means a lot of exact names,such as silicon,silicone,silicone rubber,molding silicone,manual mold silicone,manual mold design silicone,pad printing silicone,printing silicone rubber,shoe mold silicone,RTV-2,RTV-1,room temperature vulcanization 

silicone,liquid silicone,HTV-1 silicone,mixed compound silicone,addition cure silicone,

Methyl alkenyl silicone,HTV-1,HTV-2,Hot Stamping silicone sheet,Silicone roller for printing,

silicone rubber tube,seal ring of silicone rubber,electronic potting silicone, LED viewing screen,LCD silicone,and so on.

Description 

Do you have any concrete house decoration with very deep undercut and complex pattern ? 

Do you want to make your concrete molds without any shrinkage  ?

We have best suitable silicone for you . 

Our concrete house decoration mold making silicone is mainly for concrete statue, veneer, paving, fountain, faux stone, manmade stone, GRC, Glass Fiber Reinforced Concrete (GFRC), cement and similar concrete house decoration molds making

Characteristics

*Light viscosity to make a pourable concrete silicone mold 

* Thixotropic agent is available for brushable concrete silicone molds 

*Hardness from 30 to 40 shore A 

* Excellent tensile and tear strength with high copy times 

*No shrinkage 

* Outstanding release properties 

Sales Specification (Special recommendation model code)

Marks :

* HY-640 silicone is very suitable for concrete decoration in large size with 

simple pattern for making pourable mold 

* HY-630silicone is very suitable for concrete decoration in deep undercuts 

with complex pattern by making pourable mold , Thixotropic agent is available for brushable concrete silicone molds 

Operation way(brushing)
1.Prepare all the tool for making silicone mold: plaster products, board, silicone rubber, release agent(Vaseline, soap water, detergent, liquid paraffin). then polish and smooth the plaster products,clean the surface and dry it for if you do not do that,the silicone mold will be striate and unsmooth.when you finished it, Choose the right parting mold-line, normally the mold can be made 

in two pieces and also can be multi-pieces for complex products, then it is better for us to draw the molded line on the model(Notes: position the mold line on the top of the model when drawing, and run around the face and eyes of the animal model as much as possible.). Then we need to brush the release agent on the plaster products and board to make it easy to demould.

2. Weight Part A and Part B in Electronic scale according to the mixing ration. The mixing ration of the condesation cure silicone rubber is 100:4 and the mixing ration of the addition cure silicone rubber is 1:1 or 10:1. It must be accurate for if it's wrong, it will cause the problem of uncure. For example: For condesation cure silicone rubber, we take 100g part A, then we need to take 4g part B to mix it. For addition cure silicone rubber, we take 100g part A, we need to take 10g or 100g part B to mix it, which depends on the mixing ration is 1:1 or 10:1.

3.Mix part A and part B evenly. If no, the silicone mold will be partly solidified. what's more, it will affect the duplication times, even causing the waste of silicone rubber, which means that we need to take the new material to do the silicone mold again.

4.Vacuum pumping under-0.1mpa. To make the silicone mold perfect, we need to use vacuum machine to release the air bubbles. we put the mixtuer into vacuum machine when we mix it evenly for 3-5mins. If the time is too long, it will cause cross linking reaction,which means the silicone cured in the vacuum machine and we need to take the new material to do the silicone mold again.

(PS: if we do not have vacuum machine, there is two way to relese the bubble. First, we can extend the operating time of the silicone rubber, letting it contact the air. it will be better. Second, for the condensation cure silicone rubber, we can reduce the mixing ratio of catalyst from 4% to 2-3%, then the reaction of mixture( part a and part b) will be slower and the bubble will be exhausted by itself.

5.Brushing,first layer. when finished the step 4, then webrushing the silicone rubber on themold.Normally the first layer is brushed thinly to cover the model and the clay, so it should not be too thick.(PS: we must brush the silicone evenly, otherwise it can not replicate the pattern completely and affect the beauty of the products)

6. Brushing, the secondlayer.Brush the second layer of silicon rubber till 

the first one is cured. Normally the second layer should be 3-5mm,

Cover a gauze or cloth on it when the second cross linking reaction goes on, and use a brush pen or a brush to avoid any interstices. Evenly brush the third layer of mixed silicon rubber on the gauze or cloth This step will longer the mold using age, tear-strength,tension strength and duplication times.

(PS: according to the size of the products, add one more layer of gauze. Usually, it will not cover more than 2 layers of gauze) 

7. Outer mold. After the silicone cured, then we can make a outer mold for plaster.

Way 1: Make a square frame with four pieces of wooden boards, and make sure the wooden boards are fixed firmly, then pour the mixed liquid plaster(or other material) into the frame. Shave the plaster-made outer mold with a scraper 

when the plaster is going to cured.

Way 2: brushing resin on the surface after silicone mold, Cover a gauze or cloth on it, then brushing the resin again. Repeat the operation for 2-3 times

9.Demoulding. If the operate time is 30-40 mins, then the curing time will be 4-5hrs under 25 degree. Usually the cure time is the 6 times of the operate time. so after 4-5 hrs later,we can demould the silicone mold. but we s est that it will be better to use it after 24 hrs.(ps: if we want the silicone mold looks beautiful, we can use the scissors to trim it). 

Questions & Answers

Question:How many kgs of silicone i need to make a mold, like 1m*1m?

Answers: First, you change the "m" to "cm" . then the V(volume)=100cm(length)*100cm(width)*1.5cm(height or thickness) =15000cm3

→ the density of the liquid silicone is 1.1g/cm3→ the quantity= 15000cm3
* 1.1g/cm3=16500g(16.5kg) 

Question: How can i know the thickness of the silicone mold?

Answers: For the pouring way, if you do not have a plaster have a base to keep its shape(like square),then we usually s est that  2-3cm is enough. If yes, then 1-1.5 cm enough.

Question:  Why is there not enough 25kgs silicone in the drum? 

Answers: V=m/p. because the different of the silicone viscosity, so there will be a little diffenrence. when the viscosity is lower, there will be 26kgs or more. In contrast, there will be 24kgs or little.

Question: How can I know this silicone is suitable for my products?

Answers: For example, For plaster mold, we usually s est that using Shore A 20-30( plaster products is easy to deform, so we use soft silicone to make molds). For concrete, we use Shore A 30-40. Then we decide the specific one according to the product's size.

Any interest, free sample are avaible for your testing, JoJo is here at your service

 Shenzhen Hong Ye Jie Technology Co., LTD.

Tel: 86-755-89212380

Fax: 86-755-89948030

Mob: 86-18938867553

Email: hyxz(at)szrl.net

Skype: siliconerubber(at)outlook.com

Website: www.szrl.net