Use of hydrophilic organomodified siloxanes as a processing aid for melt granulation
View Patent ↗Use of organomodified polysiloxanes which have at least three different polyether radicals, at least two of these polyether radicals differing by at least 9% by mass in the proportion of ethylene oxide units therein in the total weight of the polyether radical, as a release agent or release agent constituent in melt granulation.
1. A method for producing melt granules comprising:
providing at least one substance for granulation;
heating said at least one substance for granulation to provide a melt of said at least one substance; and
cooling said melt of said at least one substance in the presence of at least one organomodified polysiloxane of formula (I)
where
a+b+c+d+2=20 to 210,
a=15 to 205,
b=1 to 12,
c=1 to 12,
d=1 to 12,
the R radicals are each independently identical or different, aliphatic or aromatic hydrocarbyl radicals having 1 to 10 carbon atoms,
the R4 radicals are each independently identical or different R, R1, R2 or R3 radicals,
the R1, R2 and R3 radicals are each independently different polyether radicals of general formula (II)
where
e is 3 to 11,
f is 6 to 30,
g is 0 to 15,
h is 0 to 5,
i is 0 to 5, and
R5 are independently the same or different and are each a methyl, acetyl or hydrogen radical.
2. The process of claim 1 , wherein the polyether radical of formula (II) has a molecular weight greater than 200 g/mol.
3. The process of claim 2 , wherein the proportion of ethylene oxide in said polyether radical of formula (II) is greater than 45% by mass, and the percentage by mass of ethylene oxide in the polyether radical R2 is at least 9% by mass greater than the percentage of ethylene oxide in the polyether radical R1, based in each case on the polyether radicals of formula (II).
4. The process of claim 3 , wherein the radicals of formula (II) may each be formed randomly, in a gradient or in blocks.
5. The process of claim 1 , wherein the organomodified polysiloxanes of formula (I) are present in an aqueous solution.
6. The process of claim 5 , wherein said aqueous solution comprises from 0.5 to 50% by weight of said at least one organomodified polysiloxane of formula (I).
7. The process of claim 1 , wherein the at least one organomodified polysiloxane has a cloud point from 35° C. to 60° C.
8. The process of claim 1 , wherein said at least one substance for granulation is sulfur.
9. The process of claim 1 , wherein the melt is applied to a moving belt, and said moving belt is a steel belt cooler.
10. The process of claim 9 , wherein said at least one organomodified polysiloxane of formula (I) is applied to the moving belt before applying said melt to the moving belt.
11. The process of claim 10 , wherein said at least one organomodified polysiloxane of formula (I) is applied to said moving belt by spraying.
12. The process of claim 10 , wherein said at least one organomodified polysiloxane of formula (I) is applied continuously to said moving belt.
13. The process of claim 1 , wherein said at least one organomodified polysiloxane of formula (I) is employed as a sole release agent.
14. The process of claim 1 , wherein said at least one organomodified polysiloxane of formula (I) is prepared by hydrosilylation of an unsaturated polyether and a SiH-functional siloxane.
15. The process of claim 1 , wherein said at least one organomodified polysiloxane of formula (I) is used in conjugation with a solvent, said solvent is selected from water or an alcohol.