US 10,308,739 B2Granted

Method for preparing polyvinyl chloride by suspension and polymerization, and feeding device

AssigneeAmos Chemicals Inc.

InventorsYuhai Gao, Xianzhen Zhuo

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Abstract

The present invention provides a production method of polyvinyl chloride by suspension polymerization and a feeding apparatus. This method comprises: Step 1: injecting a vinyl chloride monomer and water at 25-98° C. into a reaction vessel to obtain a water suspension, closing the reaction kettle, repeatedly and cyclically performing vacuum-pumping and cleansing with nitrogen, stirring and evacuating oxygen in the reaction kettle; Step 2: adding a first suspension agent and a second suspension agent into the reaction kettle, and then adding a nanopowder and an initiator composite, to carry out the polymerization reaction; Step 3: adding cold water to terminate the polymerization reaction upon the pressure in the reaction kettle is reduced to 3.5 bar or less; Step 4: evacuating and vacuumizing the reaction kettle, and then filtering, washing and drying the resulted polymer, to obtain polyvinyl chloride. The present invention also provides a feeding apparatus used for the above production method. Polyvinyl chloride produced by the method of this invention has good performance and can meet the requirements of physical and chemical properties and applicability for most applications.

Claims20

Dependent claims

A method of producing polyvinyl chloride by suspension polymerization, comprising:

a) injecting a vinyl chloride monomer and water at 25° C. to 98° C. into a reaction kettle to obtain a water suspension, closing the reaction kettle, repeatedly and cyclically performing vacuum-pumping and cleansing with nitrogen, stirring, to evacuate oxygen in the reaction kettle;
b) adding a first suspension agent and a second suspension agent into the reaction kettle, and then adding a suspension stabilizer and an initiator composite, to carry out the polymerization reaction;
c) adding cooling water to terminate the polymerization reaction when the pressure in the reaction kettle is reduced to 3.5 bar or less;
and
d) evacuating and vacuumizing the reaction kettle, and then filtering, washing and drying the resulted polymer, to obtain polyvinyl chloride;
wherein, the vinyl chloride monomer and water are in a ratio by mass of 1:3-1:0.5;
the first suspension agent is a polyvinyl alcohol having an alcoholysis degree of 95-66%, and the second suspension agent is a polyvinyl alcohol having an alcoholysis degree of 80-60%;
the starting materials of the initiator composite include chloroformate, peroxide, organic acid anhydride and sodium hydroxide in a ratio by mass of 3-7:0.5-1.5:0.5-2:2-4;
the first suspension agent is added at an amount of 200-500 ppm, the second suspension agent is added at an amount of 800-1000 ppm, the suspension stabilizer is added at an amount of 2800-3300 ppm, the initiator composite is added at an amount of 2700-3600 ppm, relative to the mass of the vinyl chloride monomer.

6 more elements

A feeding apparatus for producing polyvinyl chloride by suspension polymerization, comprising:

a peroxide vessel, a peroxide storage tank, a sodium hydroxide solution vessel, a sodium hydroxide solution storage tank, a chloroformate storage drum, an organic acid anhydride storage drum, a waste liquid tank, a washing tower, a box for automatic handling of drums contained therein, and an inlet pipe for starting material water;
the peroxide solution vessel is connected to the peroxide storage tank by a first pump, and the peroxide solution storage tank is connected to the inlet pipe for starting material water by a first feeding pump;
the sodium hydroxide solution vessel is connected to the sodium hydroxide solution storage tank by a second pump, and the sodium hydroxide solution storage tank is connected to the inlet pipe for starting material water by a second feeding pump;
the chloroformate storage drum and the organic acid anhydride storage drum are arranged in the box for automatic handling of the drums, wherein the box is provided with an exhaust ventilation device, a blower and a vertical pump;
the blower is connected to the washing tower, and the vertical pump is connected to the waste liquid tank;
one end of the inlet pipe for starting material water is used for inputting the starting material water, and the other end thereof is connected to the top of a reaction kettle;
the chloroformate storage drum is connected to the inlet pipe for starting material water by a third feeding pump, and the organic acid anhydride storage drum is connected to the inlet pipe for starting material water by a fourth feeding pump;
the bottom of the washing tower is connected to the waste liquid tank;
the waste liquid tank is provided with a sodium hydroxide inlet pipe;
the waste liquid tank is connected to the outside of the apparatus by a fourth pump.

7 more elements

Dependencies are inferred from the claim text.

Facts

Application: 15/533,605Filed 11 Feb 2015
Priority: CN 2014 1 085319631 Dec 2014
Published: US 2017/0349680 A17 Dec 2017
Granted: 4 Jun 2019
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

C08F 114/06
Monomers containing two carbon atoms: vinyl chloride
B01J 4/00
Feed or outlet devices
B01J 4/001
Feed or outlet devices; Feed or outlet control devices: feed or outlet devices as such, e.g. feeding tubes
C08F 2/01
Processes of polymerisation: characterised by special features of the polymerisation apparatus used

Family

US 2017/0349680 A1Pre-grant publication · published 7 Dec 2017
US 10,308,739 B2This patent

From the US filing history. Foreign family members aren’t listed.

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