2. What are Rubber Tackifying Resins?
In this post, We will discuss the different types of rubber tacking resins made available to the market and why they are so important in the production of high-performance rubbers such as NR, SBR, BR, CR, IIR, and EPDM.
3. What are They Used For?
What are rubber tackifying resins and how are they used for?
Rubber tackifying resins are a set of polymers (usual polymers with a large number of repeating units, both in the monomeric and oligomeric forms) that form a rubber composition when mixed with a suitable resin. The polymeric composition is usually characterized by the degree of crystallinity, which is affected by the extent to which the repeating units cross-link to form molecules.
In general, sintered rubber compositions can be made from any solid polymer that can be molded into a cast or extruded into a sheet; e.g., polytetrafluoroethylene (PTFE), polypropylene, polyethylene terephthalate (PET), etc.
The homopolymerized co-polymerization of PTFE and PET has been recognized as one of the most important industrial rubber materials since it was first investigated in Japan in 1955. In Japan, PTFE is mainly used as an extruder material for extrusion machines such as vulcanizers and extruder heads; PET is mainly used as an extruder material for extrusion machines such as sintered belts. Both materials have slight differences in their physical properties—e.g., pore size, crystallinity—as well as their mechanical properties such as toughness and tensile strength. To improve both mechanical properties and pore size, PTFE has been extensively modified through copolymerization with other RuO 2 -containing monomers such as acrylic acid esters (AAEs). This process has been referred to as “rubberizing” because it involves the addition of RuO2 groups at various locations on an AAE backbone chain to polymerize it; this RuO 2 group becomes polymerized in situ during the copolymerization reaction. The resulting random copolymers have different pore sizes, crystallinity, and mechanical properties compared to those obtained using non-rubberized AAEs alone.
In other words: As far as we know PTFE is the first polymer that can be tackified by the addition of RuO2 groups without any chemical crosslinking processes necessary—a property known since 1955. There have been many attempts to develop rubbers containing additional RuO2 groups for various applications, but most were based on aliphatic or aromatic monomers or containing less than 10% RuO 2.
4. How Do They Improve Rubber Mixing?
Rubber tackifying resins manufacturers are designed to bond two types of components together: hard and soft. They are used for the manufacturing of a variety of products including rubbers, urethane resins, and elastomers. In addition to improving product uniformity, they can also improve the starting temperature and thermal stability of the compound.
Rubber tackifying resins are one of several materials that can be used to bond two or more different types of materials together.
5. What Types of Rubbers Can They Be Used With?
The main types of rubbers that might be tackified with China rubber tackifying resins include:
- SBR – Used mainly to make EPDM (thermoset elastomer)
- SR – Used mainly to make SBR (thermoset elastomer)
- CR – Used mainly to make CR (thermoset elastomer)
What’s interesting about these four common surfaces we use is that they have similar “preferential” cross sections which can result in different properties during curing or loading. There is a lot more work to do in this area but it is an area where we have some direction and some interactions among rubbers and is likely going to improve over time as new developers test out new combinations.
The following is a summary of some common rubber tackifying resins from China factory that are used in the manufacturing of rubber materials, especially for NR and USP.
They can be used as line or cross-linking agents, curing and diffusion promoting agents, mold release agents, impact additives in the rubber industry, etc.
Rubber tackifying resins:
- Rubber tackifying resin (RTR) (polyvinyl alcohol)
rubber tackifying resins
- Unidimensional cure forming agent [USP]
- Carbon black curing agent [USP]
- Retarder [USP]
- Abrasive powder [USP]
- Tack curing agents/erasers [USP]
- Acrylic adhesive/adhesive powder [USP]
Acrylic adhesives: (1) 1-2% part polydimethylsiloxane (PDMS), 2% PVA, 2% polyurethane, and 0.5% EDTA. The product can be solid, semi-solid, or liquid. One set of polymers is used for each color on the printing plate. The flexibility is controlled by the amount of PDMS/polyurethane mix and the hardness as well as by the type of plasticizer to be added to the polymers. The required curing temperature is 55 – 60˚C and the required curing time is 1 – 5 minutes. The color density is ±10%. The required curing temperature range may vary depending on the type of plasticizer selected. Color density should be controlled depending on solvent composition; solvent may vary between colors in different colors printed using different types of films. Color can also vary depending on ambient temperature during the printing process; higher temperatures will produce darker colors with smaller variations in color density for all colors printed through the same film system at the same time. Can be supplied in either solid or slurry form. Often referred to as RTR (rubber tackifier resin), or UTR (ultra-tackifier resin). RTR is a thermoplastic that consists of two monomers: PDMS with a pH from 2 to 8 are miscible with basic pH neutralizing solutions such as NMP (pH neutralizing agent), TWEEN80 (tween 80), or Triton X100 (triton X100).