Search results
Results from the WOW.Com Content Network
Curing is a chemical process employed in polymer chemistry and process engineering that produces the toughening or hardening of a polymer material by cross-linking of polymer chains. [1] Even if it is strongly associated with the production of thermosetting polymers , the term "curing" can be used for all the processes where a solid product is ...
The problem of heat transfer is compounded by the highly exothermic nature of free radical addition polymerization. The polymerization is obtained with a broad molecular weight distribution due to the high viscosity and lack of good heat transfer.
Van 't Hoff plot for an exothermic reaction. For an exothermic reaction, heat is released, making the net enthalpy change negative. Thus, according to the definition of the slope: =, For an exothermic reaction Δ r H < 0, so
N 2 (g) + 3 H 2 (g) ⇌ 2 NH 3 (g) ΔH = −92 kJ mol −1. Because this reaction is exothermic, it produces heat: N 2 (g) + 3 H 2 (g) ⇌ 2 NH 3 (g) + heat. If the temperature were increased, the heat content of the system would increase, so the system would consume some of that heat by shifting the equilibrium to the left, thereby producing ...
In vulcanization, sulfur is the cross-linking agent. Its introduction changes rubber to a more rigid, durable material associated with car and bike tires. This process is often called sulfur curing. In most cases, cross-linking is irreversible, and the resulting thermosetting material will degrade or burn if heated, without melting.
Glutaraldehyde is an organic compound with the formula (CH 2) 3 (CHO) 2.The molecule consists of a five carbon chain doubly terminated with formyl (CHO) groups. It is usually used as a solution in water, and such solutions exists as a collection of hydrates, cyclic derivatives, and condensation products, several of which interconvert.
Silanization is the attachment of an organosilyl group to some chemical species. Almost always, silanization is the conversion of a silanol-terminated surface to a alkylsiloxy-terminated surface.
The initial result was disappointing as reaction of CpTa(=CH−t−Bu)Cl 2 with ethylene yielded only a metallacyclopentane, not metathesis products: [44] But by tweaking this structure to a PR 3 Ta(CHt−bu)(Ot−bu) 2 Cl (replacing chloride by t-butoxide and a cyclopentadienyl by an organophosphine, metathesis was established with cis-2 ...