CN101445582B

CN101445582B - Method for recycling and regenerating waste polyurethane resin

Info

Publication number: CN101445582B
Application number: CN2008102444980A
Authority: CN
Inventors: 武春余; 惠坚强; 吴兴保
Original assignee: HEFEI ANLI POLYURETHANE NEW MATERIAL CO Ltd
Current assignee: HEFEI ANLI POLYURETHANE NEW MATERIAL CO Ltd
Priority date: 2008-12-10
Filing date: 2008-12-10
Publication date: 2010-10-06
Anticipated expiration: 2028-12-10
Also published as: CN101445582A

Abstract

The invention relates to a method for recycling and regenerating waste polyurethane resin. The method comprises the following steps: the waste polyurethane is recycled form the waste solution and then regenerated, and the recycled polyurethane performs synthetic reaction with polyhydric alcohol E1 or/and polyhydric alcohol E2, diphenylhydrazine vulcabond, phosphoric acid and catalyst (stannous octoate) in the DMF solvent at the temperature of 70 to 80 DEG C until the viscosity is 100 to 200 Pa.s/25 DEG C and the solid content is 30 to 40 percent. The invention has the advantages that the problem of waste recycling for the polyurethane resin solution is solved; the regenerating polyurethane resin has the versatile characteristic of the common polyurethane resin and is used for production of synthesizing leather; and not only the environment is protected, but also the production cost is reduced.

Description

The method of a kind of recovery, regenerating waste polyurethane resin

One, technical field

The present invention relates to the method for a kind of processing " three wastes ", particularly the treatment process of waste liquid exactly is the method for recovery in the discarded liquid of urethane resin, regenerating waste polyurethane resin.

Two, background technology

Urethane resin is the novel material that reaches widespread use in recent years, owing to contain the hardness that the rigidity characteristic of phenyl ring and carbamate groups formation provides polyurethane material in its structure; Containing the long carbochain component of a large amount of flexibilities simultaneously in the segment provides the toughness and the crooked softish feature of material; In the effect that is used for having aspect the artificial synthetic leather similar corium, can well substitute corium at the footwear material, aspects such as case and bag, sofa, furniture, automobile decoration are used, and reclaim the every performance index of depleted urethane resin and descend in synthetic leather is produced, and can not satisfy the needs that synthetic leather is produced.

Three, summary of the invention

The present invention is intended to recycle depleted urethane resin (PU) in the synthetic leather production, and technical problem to be solved is that the PU that reclaims is regenerated, and makes it to satisfy the requirement that synthetic leather is produced.

The PU of use for synthetic leather mostly is solvent-borne type, and depleted PU is dissolved in N more, in dinethylformamide (DMF) solvent.The thinking of present method is Separation and Recovery PU in waste liquid at first, and then is regenerated.

Present method comprises separation, dry and regeneration, and described separation is a thin up in waste liquid, and that utilizes PU water-insolublely makes it cohesion and separate out, and by leaving standstill it is separated out fully, the solid material PU that separation then, fragmentation, drying and dehydrating obtain reclaiming.

Described regeneration is that the solid material PU that reclaims is regenerated.Specifically solid material PU is dissolved among the DMF, synthesizes under the catalyzer existence condition with polyvalent alcohol, vulcabond, phosphoric acid then, the PU that obtains regenerating is used to produce synthetic leather.

Described polyvalent alcohol is selected from ethylene glycol or butyleneglycol or hexylene glycol etc. (calling polyol E 1 in the following text), perhaps be selected from polyester polyol, as polyethylene glycol adipate or poly adipate succinic acid ester or poly-adipate glycol butanediol ester etc., perhaps polyether glycol such as polytetrahydrofuran diol (PTMEG) etc.Polyester polyol or polyether glycol (calling polyol E 2 in the following text) require molecular weight 1500～3000, hydroxyl value 37～75mgKOH/g.

Described vulcabond is selected from diphenylmethanediisocyanate (MDI)

Described catalyzer is selected from stannous octoate.

Each component has following proportioning:

Material name proportioning (weight part)

The PU solid material 100 that reclaims

Polyol E 1 1～10

Polyol E 2 0～30

N, dinethylformamide 150～300

Diphenylmethanediisocyanate 5～50

Phosphoric acid 0.001～0.01

Catalyzer 0.01～0.1.

Described N, dinethylformamide comprise the used amount of dissolved solids material PU.

Concrete processing step is as follows:

(1), raw-material processing: collect the polyurethane resin solution waste, add water (can be clear water or N, the aqueous solution of dinethylformamide 0～20% following concentration) dilution, soak, separate then, urethane resin is condensed into the solid material.Solvent enters in the water, sends into solvent recovering system;

(2), fragmentation: the solid material is sent into plastic breaker, is broken into the fritter of weight less than 20g;

(3), drying: the solid material of fragmentation is carried out drying, make the solid material contain moisture≤500ppm, sprawl as far as possible and stir the solid material, accelerate rate of drying.

(4), stirring and dissolving: add solvent N earlier in reactor, dinethylformamide starts stirring, heats up 40～60 ℃, adds the solid material again, maintains the temperature at 40～60 ℃ of following stirring and dissolving; 100 parts of solid material are dissolved among 100～150 parts of DMF.

(5), filter: blowdown is filtered with 120 or 200 mesh filter screens in the dissolving back, obtain reclaiming the DMF solution (calling the intermediate material in the following text) of PU, that detects the intermediate material decides to stretch modulus (sign soft durometer), and routinely, to determine that polyol E 1 is or/and modulus to 6～8MPa is stretched in the ingredient proportion adjustment of polyol E 2 surely.

(6), reaction: with the intermediate material, catalyzer, polyol E 1 be or/and polyol E 2, and phosphoric acid adds in the reactor and reacts; 70～80 ℃ of control temperature of reaction kettle add diphenylmethanediisocyanate in batches; When viscosity reaches 200～300Pa.s/25 ℃, can add N, dinethylformamide dilutes, and divides 1～3 adding to dilute, and as requested, adjusts viscosity to 100～200Pa.s/25 ℃, solid content 30～40%;

(7), the cooling, blowdown: viscosity after solid content is qualified, is cooled to below 60 ℃ and filters blowdown.

Institute of the present invention adopting process method has been compared following advantage with existing processing method: this process using waste polyurethane resin solution is main raw material; solve the polyurethane resin solution waste and reclaimed problem; and the purpose that reaches environment protection and reduce production costs; this product quality has the universal performance of common polyurethane resin; satisfy synthetic leather and produce the general characteristic of required urethane resin requirement, be used for the production of synthetic leather.

Four, embodiment

Non-limiting examples is stated as down:

1, the preparation of intermediate material

Add solvent N earlier in reactor, 100 parts of dinethylformamides start stirring, be warming up to 40～60 ℃, add 100 parts in solid material again, add several times, observing response still motor load, load reach 60% o'clock of rated load to be stopped to feed in raw material, and even load continues to feed intake after descending again.Keep temperature 40～60 ℃ of following stirring and dissolving again; Stirring and dissolving is finished in general two hours, and sampling is observed as the blowdown of can lowering the temperature after all dissolving.Filter and adopt 120 or 200 mesh filter screens to filter blowdown, obtain the intermediate material.And detect and stretch modulus surely.

2, regeneration PU is synthetic

(1) when detected value be 100% when stretching modulus 3.0Mpa surely, feed intake in following ratio:

Material name proportioning (weight part)

Intermediate material 200

Polyol E 1 (ethylene glycol) 5

Polyol E 20

N, dinethylformamide 140

Diphenylmethanediisocyanate 25

Phosphoric acid 0.003

Catalyzer (stannous octoate T-9) 0.03.

With the intermediate material: 200 parts, ethylene glycol: 5 parts, phosphoric acid: 0.003 part, drop in the reactor, agitation condition drops into diphenylmethanediisocyanate down: 20 parts, the intensification control reaction temperature is 70～80 ℃, add catalyzer T-9:0.03 part, add diphenylmethanediisocyanate (MDI) behind reaction 40～60min gradually: 25 parts of accumulative totals, and when viscosity reaches a certain amount of, use N, dinethylformamide (DMF) stepwise dilution: 140 parts of accumulative totals.Final control material touches the mark requirement: viscosity 120Pa.s/25 ℃, solid content: 35%.Cool then to filtering blowdown below 60 ℃, can obtain the PU that regenerates, 100% stretches modulus surely is increased to 6.0～8.0Mpa, satisfies the requirement of synthetic leather processed and applied.

(2) when detected value be 100% when stretching modulus 12.5Mpa surely, feed intake in following ratio:

Material name proportioning (weight part)

Intermediate material 200

Polyol E 1 (ethylene glycol) 1

Polyol E 2 (ethylene glycol adipate(EGA), molecular weight: 2000) 35

N, dinethylformamide 180

Diphenylmethanediisocyanate 15

Phosphoric acid 0.003

Catalyzer (stannous octoate T-9) 0.03.

With the intermediate material: 200 parts, ethylene glycol: 1 part, polyol E 2:35 part, phosphoric acid: 0.003 part, drop in the reactor, agitation condition drops into diphenylmethanediisocyanate down: 10 parts, the intensification control reaction temperature is 70～80 ℃, adds catalyzer T-9:0.03 part.Add diphenylmethanediisocyanate (MDI) behind reaction 40～60min gradually: 15 parts of accumulative totals, and when viscosity reaches a certain amount of, use N, N-methylformamide (DMF) stepwise dilution: 180 parts of accumulative totals.Final control material touches the mark requirement: viscosity 140Pa.s/25 ℃, solid content: 35%.Cool then to filtering blowdown below 60 ℃, can obtain the PU that regenerates.100% stretches modulus surely is increased to 6.0～8.0Mpa, satisfies the requirement of synthetic leather processed and applied.

Claims

1. the method for a recovery, regenerating waste polyurethane resin, it is the urethane resin of recovery, regenerating waste in waste liquid, comprise separation, fragmentation, dry and regeneration, it is characterized in that: described regeneration be exactly in waste liquid through separate, broken, be dried to the recovery urethane of water ratio≤500ppm at N, in the dinethylformamide solvent with polyol E 1 or/and the building-up reactions of the inferior tin of polyol E 2, diphenylmethanediisocyanate, phosphoric acid and octoate catalyst under 70～80 ℃ of conditions, react to viscosity 100～200Pa.s/25 ℃ solid content 30～40%; Each raw material has following parts by weight:

Reclaim 100 parts of urethane

N, 150～300 parts of dinethylformamides

1 1～10 parts of polyol Es

2 0～30 parts of polyol Es

5～50 parts of diphenylmethanediisocyanates

0.001～0.01 part of phosphoric acid

0.01～0.1 part of stannous octoate,

Described polyol E 1 is selected from ethylene glycol or butyleneglycol or hexylene glycol,

Described polyol E 2 is selected from polyester polyol or polyether glycol.

2. method according to claim 1 is characterized in that: described polyester polyol is selected from polyethylene glycol adipate or poly adipate succinic acid ester or poly-adipate glycol butanediol ester.

3. method according to claim 1 is characterized in that: described polyether glycol is selected from polytetrahydrofuran diol.