Preparation method of itaconate-butadiene bio-based engineering rubber
A preparation method of itaconate-butadiene bio-based engineering rubber belongs to the bio-based engineering rubber area. The bio-based engineering rubber of the present disclosure is formed through chemical crosslinking of copolymers, which are formed by polymerization of itaconate and butadiene emulsion. The number average molecular weight of the itaconate-butadiene copolymer is about 53000-1640000, and weight-average molecular weight is about 110000-2892000. Itaconate-butadiene copolymers are formed by polymerization of itaconate and butadiene emulsion, then and chemical crosslinking of the copolymer is performed to form bio-based engineering rubber using a traditional sulfur vulcanizing system. The bio-based engineering rubber has high molecular weights as well as lower glass-transition temperatures and can be vulcanized using the traditional sulfur vulcanizing system. The bio-based engineering rubber of the present disclosure has same physic-mechanical property as well as processability as compared to rubber prepared using conventional techniques and may be used for manufacturing tire treads and conveyor belts.
1. A method of preparing bio-based engineering rubber formed by emulsion polymerization of chemically crosslinked itaconate-butadiene copolymers, the method comprising:
A: performing the emulsion polymerization of itaconate and butadiene by:
mixing itaconate, emulsifier, electrolyte, activator and deionized water in a polymerization reactor,
closing the polymerization reactor,
removing air from the polymerization reactor using vacuum-pumping,
filling the polymerization reactor with nitrogen,
repeating mixing, closing, removing and filling operations for 1-5 times,
adding butadiene, deoxidant, and initiator to the polymerization reactor and performing reaction for 5-15 hours in the polymerization reactor under 1-20° C., 0.1-5 Mpa,
adding a terminator to terminate the reaction and performing demulsification and drying of the terminated reaction via an addition of a demulsifier to obtain a bio-based engineering elastomer raw glue comprising the itaconate-butadiene copolymers, wherein a mass ratio of the itaconate, the butadiene, the emulsifier, the electrolyte, the activator, the deoxidant and the initiator, the terminator and the deionized water is: 100: 1-100:1-10:0.1-5:0.01-5:0.1-5:0.01-5: 1-10:100-1000, a number average molecular weight of the itaconate-butadiene copolymers is about 53000-1640000, a weight-average molecular weight of the itaconate-butadiene copolymers is about 110000-2892000, and a molecular formula of itaconate is:
wherein R 1 and R 2 are H or C 1-10 alkyl, and R 1 R 2 are same or different; and
B: performing vulcanization process based on the obtained bio-based engineering elastomer using sulfur as a cross-linking agent in a sulfur vulcanizing system under 140-160° C. to prepare the bio-based engineering rubber comprising the itaconate-butadiene copolymers.
2. The method of claim 1 , wherein R1 and R2 are n-butyl, n-amyl or isoamyl.
3. The method of claim 1 , wherein the emulsifier comprises at least one of disproportionate sodium abietate, disproportionated potassium rosinate, sodium aliphatate soap, potassium aliphatate soap, sodium dodecyl sulfate, sulfate sodium dodecyl benzene sulfonate, or sodium dodecyl sulfonate.
4. The method of claim 1 , wherein the electrolyte comprises at least one of potassium chloride, potassium phosphate, ethylenediaminetetraacetic acid (EDTA), sodium m-dimethylnaphthalenesulfonate (TAOM-L), phosphate, or potassium hydroxide.
5. The method of claim 1 , wherein the activator is a mixture of sodium formaldehyde sulfoxylate and ethylenediaminetetraacetic acid (EDTA) ferric or a mixture of sodium formaldehyde sulfoxylate and ferric sodium ethylenediaminetetraacetate (NaFeEDTA) and initiator mentioned above is p-Menthane Hydroperoxide, tert-butyl hydroperoxide or cumene hydroperoxide.
6. The method of claim 1 , wherein the terminator is sodium N, N-dimethyl dithiocarbamate, sodium diethyldithiocarbamate, hydroxylamine or sodium polysulfide.
7. The method of claim 1 , wherein the mass ratio of itaconate and butadiene monomer is 100:10 to 100:60.
8. The method of claim 1 , wherein the sulfur vulcanizing system comprises vulcanization activator, vulcanization accelerator, and vulcanizator.
9. The method of claim 1 , wherein the demulsifier comprises hydrochloric acid.
10. The method of claim 1 , wherein the deoxidant comprises sodium hydrosulfite.