摘要:
A process for extracting rubber and/or resin from rubber containing plants such as guayule utilizing a monophase mixture of an organic polar solvent and a hydrocarbon solvent.
摘要:
A process and urethane composition for making urethane prepolymers from a polyisocyanate and blends of two or more urethane intermediates. The prepolymers so produced when cured have improved physical properties such as high low strain modulus and tensile strength relative to cured polyurethanes prepared from a mixture of prepolymers prepared by reacting a polyisocyanate with the component intermediates and subsequently blending the prepolymers.
摘要:
Urethane elastomers are produced by initially adding at least one incremental amount of a curing agent to a urethane prepolymer, having free polyisocyanate therein. Generally, free polyisocyanate-curing agent adducts are precipitated. Subsequently, the remaining amount of curing agent is added. Chain extension, accordingly, is favored which produces hard segment domains more evenly distributed in the polymer chain and imparts improved physical properties such as hardness, tear strength and high-low strain modulus.
摘要:
The vulcanization rate of rubber stock compounded for curing is increased by using in the stock for the cure an accelerator of certain amine-substituted esters of phosphorodithioic acid.
摘要:
The vulcanization rate of rubber stock compounded for curing is increased by using in the stock for the cure an accelerator of certain esters of phosphorodiothioic acid.
摘要:
scrap rubber is pyrolyzed in the substantial absence of air and treated with steam. The steam treatment can be carried out simultaneously with the pyrolysis or subsequently or it may be carried out both in part simultaneously with the pyrolysis and subsequently. Different products are obtained.
摘要:
Salts generally act as reinforcing compounds in polyurethane compositions. Salts containing a free-amine function generally increase the low-strain moduli more than salts which lack such free-amine functions or are neutral. The salts are generally formed by reacting a basic nitrogen function compound such as a monoamine or a diamine with a mono or a dicarboxylic acid.
摘要:
A process for achieving a high yield of rubber and/or resin from rubber containing plants such as guayule plants by crushing the plants, forming a slurry with a solvent and fine grinding said slurry with a high shear mixer. The time required by the process is very short in comparison with prior art techniques.
摘要:
Rubber, hydrocarbons, i.e., resins, and other useful by-products are extracted from shrubs such as guayule and guayule-like shrubs by a procedure wherein the shrub, after being comminuted, is processed in an aqueous and/or a non-aqueous system. An optional water treatment step can be used to remove water solubles and/or facilitate processing and achieve increased yield of desired by-products.
摘要:
Guayule plant material can be stored in an aqueous system comprising (a) communited guayule plant material; (b) water and (c) an odor inhibitor. Typical inhibitors include protanic acids, acid salts, metal oxides and metal hydroxides. These storage systems permit efficient operation of guayule processing facilities while minimizing odors often developed in stored plant material.