Effect of resin type on curing degree
The content of double bonds in the molecular chain of linear unsaturated polyester (ie, the density of double bonds)
The reactivity of UPR is usually measured by the percentage of the number of moles of unsaturated dibasic acid contained in the total number of moles of dibasic acid. The so-called high reactivity, medium reactivity, and low reactivity generally refer to: unsaturated dibasic acid. More than 70% are highly reactive; 60-30% are moderately reactive; and unsaturated dibasic acids are less than 30% are low reactivity.
The higher the content of unsaturated double bonds in the unsaturated polyester molecular chain, the higher the reactivity of the resin and the shorter the time to complete curing.
The ratio of two double bonds of a trans double bond and a cis double bond in a linear unsaturated polyester molecule. The higher the trans double bond content, the higher the degree of cure.
There should be enough styrene content in the resin. Too much or too little will make the resin cure badly.
The influence of other additives such as polymerization inhibitor in the resin.
When preserving the uncured liquid UPR, a polymerization inhibitor is added to protect the UPR product from premature gelation during storage. The free radicals released by the reaction of the initiator and the promoter are initially consumed by the polymerization inhibitor, and the polymerization inhibitor becomes a stable macromolecule and loses its ability to inhibit polymerization. Therefore, the low-reactive resin may be highly reactive because of the small amount of polymerization inhibitor added thereto, and the highly reactive resin may become less active due to the addition of a larger amount of the polymerization inhibitor. In addition, fillers, color pastes, low shrinkage additives, etc. in the resin also affect the degree of curing of the resin.
QuanZhou Neweco High Polymer Material Co.,Ltd.
Neweco is one of the leading unsaturated polyester resin manufacturers and suppliers,widely used in automobiles, ships, rail transit, wind power generation, pipe cans, heat and corrosion protection, building materials, stone repair, sanitary ware, artificial stone and other industries. Suitable for hand lay-up, spray, pultrusion, winding, molding, vacuum introduction / RTM, casting and other molding processes. Neweco Resin is committed to excellence and focuses on the application of composite materials to provide customers with comprehensive solutions.