CN105294895B - A kind of production method improving Corvic thermal stability - Google Patents
A kind of production method improving Corvic thermal stability Download PDFInfo
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- CN105294895B CN105294895B CN201510892801.8A CN201510892801A CN105294895B CN 105294895 B CN105294895 B CN 105294895B CN 201510892801 A CN201510892801 A CN 201510892801A CN 105294895 B CN105294895 B CN 105294895B
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Abstract
The invention belongs to chemical industry for making chlorine and alkali technical fields, and in particular to a kind of production method for improving Corvic thermal stability.This method specific steps are as follows: after applying kettle, start main pan feeding program, buffer is first added, sequentially add pure water and vinyl chloride monomer, dispersing agent 1, dispersing agent 2, initiator；Termination reaction is carried out to which terminator is added after reaction；Slurry in kettle is got in blow tank using discharging pump, then strips and is further dried by stripper；In above-mentioned reaction process, fatty acid zinc, which is added, and can get has high thermal stability naval stores.The present invention, by the way that fatty acid zinc is added during the reaction, preferably ensure that the performance indicators such as thermal stability, the heat ageing whiteness of Corvic product under conditions of not changing existing main production plant；By optimized production process, solves the problems, such as that insoluble matter is adhered on stripper column plate, extend cleaning cycle, saved cleaning up cost, improve plant capacity.
Description
Technical field
The invention belongs to chemical industry for making chlorine and alkali technical fields, and in particular to a kind of production for improving Corvic thermal stability
Method.
Background technique
In the prior art, Corvic product prepared by applicant (Hao Hua Aerospace PLC, BAe), downstream user are adding
There are initial coloration abilities in work application process it is poor, product whiteness is low the problems such as, and the thermal stability for improving resin can be compared with
This is solved the problems, such as well, and proposes thermostabilization more than or equal to this technical indicator of 6min.For resin thermal stability, existing skill
Art is mostly to optimize from material selection, material amounts ratio, reaction temperature etc., and obtain certain improvement effect,
But thermal stability cannot be stably reached more than or equal to 6min and stripper stable operation effect, thus it is still necessary to be further improved.
Summary of the invention
The main purpose of the present invention is to provide a kind of production methods for improving Corvic thermal stability, can solve down
User is swum during processed and applied there are initial coloration abilities the problems such as poor, product whiteness is low, while advanced optimizing
Technical solution can preferably extend maintenance period in production process.
Detailed technology scheme adopted by the present invention is described below:
It is a kind of improve Corvic thermal stability production method, the Corvic specifically such as SG3,
SG5, SG7, SG8 type etc.；This method specifically includes the following steps:
(1) after applying kettle, start main pan feeding program, buffer is first added, sequentially add pure water and vinyl chloride monomer, dispersion
Agent 1, dispersing agent 2, initiator；
(2) termination reaction is carried out to which terminator is added after reaction；Slurry in kettle is got into blow tank using discharging pump
It is interior, then strip and be further dried by stripper；
In above-mentioned reaction process, fatty acid zinc, which is added, and can get has high thermal stability naval stores；It is preferred that reacting
After fatty acid zinc compounded with terminator after be added with terminator；
Kettle described in step (1) is that such as volume is 70m3Medium-sized reaction kettle；
By quality ratio, each material ratio is in preparation process, mono- 1 ︰ of the Ti ︰ dispersing agent dispersion of Huan Chong Ji ︰ Chun Shui ︰ Lv Yi Xi
2 terminator=40 ︰ Yin Fa Ji ︰ Zhi fat Suan Xin ︰ of agent ~ 80 ︰, 30000 ~ 32000 ︰, 24500 ~ 26000 ︰, 280 ~ 360 ︰, 140 ~ 160 ︰ 80 ~
120 ︰, 5 ~ 9 ︰ 40 ~ 45；
The buffer is the ammonium bicarbonate aqueous solution that mass concentration is 9 ~ 11%, the carbon that specifically such as mass concentration is 10%
Sour hydrogen aqueous ammonium；
The dispersing agent 1 is the mixture that total mass concentration is 6.4 ~ 6.9%, and mass concentration is specifically, for example, 6.5%；Respectively
Material specifically includes the polyvinyl alcohol L-10 of alcoholysis degree 71.5~73.5%；The LW-100(solid content 40% of alcoholysis degree 39~46%)；
The hydroxypropyl methyl cellulose 65HD50 of methyl accounting 27~30%, hydroxypropyl accounting 4~7.5%；Each quality of material ratio is poly- second
1 ︰ 1 of enol L-10 ︰ LW-100 ︰ hydroxypropyl methyl cellulose 65HD50=5.9 ︰, wherein hydroxypropyl methyl cellulose 65HD50 only with
Butt meter；
The dispersing agent 2 is the polyvinyl alcohol GH-20 that mass concentration is 3.9 ~ 4.2%, and mass concentration is specifically, for example,
4.0%, the alcoholysis degree 86.5~89% of the polyvinyl alcohol GH-20；
The initiator is the mixture that total mass concentration is 11 ~ 13%, and mass concentration is specifically, for example, 12%；Mixture tool
Body includes dicetyl peroxydicarbonate two (2- ethyl) peroxide that ester (abbreviation EHP) and mass concentration are 40% that mass concentration is 40%
Change neodecanoic acid isopropyl phenyl ester；By quality ratio, (cumyl peroxyneodecanoate=2 2- ethyl) Yi Zhi ︰ of dicetyl peroxydicarbonate two
~3 ︰ 1, specifically such as 2.5 ︰ 1；
The fatty acid zinc is the fatty acid zinc that Zn content is greater than 5.5%；
The terminator is a kind of aqueous emulsion of Jiaozhuo Xin Yi Chemical Co., Ltd. oil phase content produced 38 ~ 40%
Terminator；
When fatty acid zinc and terminator compound, fatty acid zinc is added in terminator, is uniformly mixed；
In actual production, to adapt to production technology, fatty acid zinc after compounding and terminator are added with terminator charge line
Enter in reaction kettle.
For the present invention in preparing Corvic product process, creative joined fatty acid zinc, preferably solve
The problem of the thermal stability difference of naval stores, has reached thermal stability more than or equal to this technical indicator of 6min, can be preferable
It solves the problems, such as first discolouration, while improving the whiteness of product.Its main technical principle is: after fatty acid zinc is added, Ji Nengzhong
The hydrogen chloride generated in the process with absorption monomer polymerization, and unstable chlorine atom can be replaced to draw to eliminate thermal degradation with carboxylate radical
Position is sent out, thus PVC dehydrochlorination can be slowed down, and its first discolouration can be inhibited, when especially stripping and dry to polyvinyl chloride resin
Whiteness reduction has obvious inhibiting effect.
In resin preparation process, although fatty acid zinc, which is added, can preferably solve resin thermal stability problems, with rouge
Opportunity difference is added in fat acid zinc, also different for reaction system influence, and main cause has:
Firstly, since effect dehydrochlorination of the vinyl chloride by free radical in polymerization process, makes to generate conjugation pair inside PVC
Key destroys the hot property of resin；And the Cl in polymerization system-It is easy to corrode stainless steel surface, while causing condensate
It is pH relatively low, system is unstable, thus needs to be added suitable buffer such as ammonium hydrogen carbonate also during pan feeding to remain poly-
Reaction is closed to carry out in a neutral environment；It, can be with buffer ammonium bicarbonate soln if fatty acid zinc is added in advance when polymerizeing pan feeding
The carbonate that ionization generates reacts, and generates zinc carbonate precipitating not soluble in water, and PVC slurry easily adheres in stripping process
In spiral-plate heat exchanger channel and on stripper column plate.Stripping system is run one month or so, will in spiral-plate heat exchanger
Bur is accumulated, causes the reduction of slurry heat transfer effect, heat transfer temperature difference can reduce by 10 DEG C or more when serious；And it is glued on stripper column plate
Addendum thickness can reach 5mm or so, and blocks column plate hole and effective aperture is caused to reduce, and eventually lead to the raising of stripper pressure difference, sternly
Pressure difference can rise to 30kPa or more when weight, lead to stripper last row strip, would have to reduce PVC into tower slurry flow；And tower
Bur on plate easily generates red material under steam long duration of action, influences product impurity number, just needs to stop stripper at this time
Chemical cleaning column plate is carried out, stoppage in transit stripper also will affect yield, and acid solution used in chemical cleaning can be to stripper and tower pumps out
It causes to corrode, further improves the cost of production and maintenance；Secondly, fatty acid zinc is the carboxylic acid of carbon atom number less (7~9)
Salt, carboxylate radical can neutralize alcoholic extract hydroxyl group contained in polyvinyl alcohol, so that the dispersion and the effect of guarantor's glue to polyvinyl alcohol are not
Benefit, thus be added when being reacted in kettle together during pan feeding with dispersing agent, it is easy to impact final resin-oatmeal quality；
For these reasons, it is preferable that after reaction, reaction kettle is added with terminator in fatty acid zinc, thus preferably
Avoid above-mentioned technological deficiency.
In general, compared with prior art, the present invention its main feature is as follows:
1, the present invention creatively joined suitable fatty acid under conditions of not changing existing main production plant
Zinc preferably solves the problems, such as that naval stores thermal stability is poor, so that naval stores thermal stability index is more than or equal to 6min, preferably
Solve naval stores heat ageing whiteness it is low the problems such as；
2, the present invention simultaneously resin manufacturing processes are optimized, optimize fatty acid zinc be added reaction system when
Machine；Studies have shown that by it after the completion of reaction again with terminator be added reaction system when, guarantee naval stores performance it is same
When, it preferably solves the technical issues of production line maintenance cycle, extends the cleaning cycle of stripper, reduce maintenance and protect
The expense of supporting, and improves production economy benefit, and the cleaning cycle of stripper once extends to every 4 by original cleaning in every 1 ~ 2 month ~
June, cleaning was primary, and plant capacity is improved, for producing 200000 tons of process units per year, what year can be voluminous 400 tons
Corvic product has preferable economic benefit.
Detailed description of the invention
Fig. 1 is the process flow chart before production technology optimization；
Fig. 2 is the process flow chart after production technology optimization.
Specific embodiment
Explanation is further explained to the application below with reference to embodiment.
It should be noted that company standard " the Q/HHYH 001-2011 suspension according to applicant (Hao Hua Aerospace PLC, BAe)
Method Corvic ", the credit rating specification of SG5 type polyvinyl chloride resin is classified as follows shown in table in following embodiments:
By taking the polyvinyl chloride resin production technique of applicant (Hao Hua Aerospace PLC, BAe) as an example, as shown in Figure 1, existing polychlorostyrene second
The olefine resin technological process of production are as follows:
Kettle is applied first, then starts main pan feeding program, the buffer of specified amount is added, sequentially add pure water and vinyl chloride list
Body, dispersing agent 1, dispersing agent 2, initiator；
Finally, the terminator to which formula ratio is added after reaction carries out termination reaction, it will be in kettle using discharging pump
Slurry is got in blow tank, then is stripped and be further dried by stripper；
It is to be understood that when producing Corvic product in this approach, by adjusting reaction temperature, reaction duration
Etc. parameters can be prepared by the Corvic product of the different sizes model such as SG3, SG5, SG7 or SG8 type.Due to different rule
The preparation of lattice Corvic product and non-present invention main innovation point, thus only with specific in following embodiments
Illustrate technical solution of the present invention and technical effect for SG5 type polyvinyl chloride resin.
Embodiment 1
For the technological process of production after polyvinyl chloride resin production process modification as shown in Fig. 2, specific as follows:
(1) after applying kettle, start main pan feeding program, buffer is first added, sequentially add pure water and vinyl chloride monomer, dispersion
Agent 1, dispersing agent 2, initiator；
(2) termination reaction is carried out to which the fatty acid zinc compounded and terminator are added after reaction；It will using discharging pump
Slurry is got in blow tank in kettle, then is stripped and be further dried by stripper；
By taking the production process of SG5 type polyvinyl chloride resin as an example, the above process is described in further detail as follows:
(1) in 70m3Reaction kettle in, after applying kettle, start main pan feeding program, when pan feeding sequentially add 60kg buffer,
31t pure water and 25.5t vinyl chloride monomer, 285 kg dispersing agents 1,150 kg dispersing agents 2,90 kg initiators；
(2) 56.5 DEG C of 300 ~ 350min(of polymerization reaction are with variation of ambient temperature appropriate adjustment, the reaction time in the present embodiment
For 320min), the compound of 40 kg terminators and 6 kg fatty acid zincs is added after reaction；By fatty acid zinc and terminator
Uniformly mixed compound is added using terminator charge line；
Finally slurry in kettle is got in blow tank using discharging pump, then is stripped and is further dried i.e. by stripper
It can.
In above-mentioned steps:
The buffer is the ammonium bicarbonate aqueous solution that mass concentration is 10%；
The dispersing agent 1 is the mixture that total mass concentration is 6.6%, specifically includes the poly- of alcoholysis degree 71.5~73.5%
Vinyl alcohol L-10；The LW-100(solid content 40% of alcoholysis degree 39~46%)；Methyl accounting 27~30%, hydroxypropyl accounting 4~7.5%
Hydroxypropyl methyl cellulose 65HD50；For hydroxypropyl methyl cellulose 65HD50 only in terms of butt, mass ratio is polyvinyl alcohol L-
10 ︰ LW-100 ︰ hydroxypropyl methyl cellulose 65HD50=5.9 ︰, 1 ︰ 1；
The dispersing agent 2 is the polyvinyl alcohol GH-20 that mass concentration is 4.1%, the alcoholysis of the polyvinyl alcohol GH-20
Degree 86.5~89%；
The initiator is the mixture that total mass concentration is 12%, which includes the peroxidating that mass concentration is 40%
Two carbonic acid two (2- ethyl) cumyl peroxyneodecanoate that ester and mass concentration are 40%；By quality ratio, peroxidating two
(the 2- ethyl) Yi Zhi ︰ cumyl peroxyneodecanoate=2.5 ︰ 1 of carbonic acid two；
The fatty acid zinc and terminator of the compounding are had by Zn content beneficial chemical industry prosperous greater than 5.5% fatty acid zinc and Jiaozhuo
The aqueous emulsion terminator that a kind of oil phase content produced is limited 38 ~ 40% compounds；Fatty acid zinc is compounded in terminator
It is interior, and after being uniformly mixed, terminator charge line is utilized in production process, fatty acid zinc is i.e. with termination at the end of reaction
Agent is added in kettle simultaneously.
Embodiment 2
As preparation method in embodiment 1 identical, only the dosage of fatty acid zinc, each material is added in appropriate adjustment to the present embodiment
Additional amount are as follows:
In 70m360kg buffer, 31t pure water and 25.5t vinyl chloride monomer, 285 kg dispersion are sequentially added in reaction kettle
Agent 1,150 kg dispersing agents 2,90 kg initiators；
Polymeric reaction temperature is 56.5 DEG C, and 40 kg terminators and 7 kg fatty acid zincs are added after reaction；
The concrete type of each material is the same as embodiment 1.
Embodiment 3
Identical as the preparation method in embodiment 1, only the dosage of fatty acid zinc, each object is added in appropriate adjustment to the present embodiment
Expect additional amount are as follows:
In 70m360kg buffer, 31t pure water and 25.5t vinyl chloride monomer, 285 kg dispersion are sequentially added in reaction kettle
Agent 1,150 kg dispersing agents 2,90 kg initiators；
Polymeric reaction temperature is 56.5 DEG C, and 40 kg terminators and 8 kg fatty acid zincs are added after reaction；
The concrete type of each material is the same as embodiment 1.
Comparative example 1
(that is, prior art) identical as the preparation method of embodiment 1, this comparative example are that fatty acid zinc is not added, respectively
Material additional amount are as follows:
In 70m360kg buffer, 31t pure water and 25.5t vinyl chloride monomer, 285 kg dispersion are sequentially added in reaction kettle
Agent 1,150 kg dispersing agents 2,90 kg initiators；
Polymeric reaction temperature is 56.5 DEG C, and 40 kg terminators are added after reaction；
The concrete type of each material is the same as embodiment 1.
Comparative example 2
It is identical as the preparation method of embodiment 1, this comparative example be added in advance when polymerizeing pan feeding fatty acid zinc (that is,
Before process modification, it is added after Tu kettle), each material additional amount are as follows:
In 70m36 kg fatty acid zincs, 60kg buffer, 31t pure water and 25.5t vinyl chloride list are sequentially added in reaction kettle
Body, 285 kg dispersing agents 1,150 kg dispersing agents 2,90 kg initiators；
Polymeric reaction temperature is 56.5 DEG C, and 40 kg terminators are added after reaction；
The concrete type of each material is the same as embodiment 1.
In this embodiment, due to not optimized to production technology, in actual motion, since fatty acid zinc is to mention
Preceding addition is easy to react with the polyvinyl alcohol in the dispersing agent 1 of addition, dispersing agent 2, influences the evenly dispersed of material；Together
When fatty acid zinc be easy to alkalinity buffer ammonium hydrogen carbonate react, generate insoluble matter be adhered to stripper column plate and spiral
In sheet heat exchanger channel.Statistics, which shows to run bur thickness on one month or so column plate, just can reach 5mm or so, be at this time
It need to be cleared up, otherwise be easy that there are Safety Risk in Production.Although tree with preferable thermal stability is obtained using the technique
Fat prod, but Production-Line Maintenance maintenance is more frequent, exerts a certain influence for production run.
The polyvinyl chloride resin gone out produced in the various embodiments described above is detected according to respective standard, as a result as shown in the table:
。
As can be seen from the above table, the present invention in prior art by being added fatty acid zinc, (comparison compared to the prior art
Example 1), SG5 type polyvinyl chloride resin prepared by each embodiment (embodiment 1 ~ 3, comparative example 2) has preferably reached the grade of special quality product
Specification, especially thermal stability index can better meet user demand.But for actual production operation, production technology is excellent
Before change, since fatty acid zinc is added in advance, after running for a period of time, bur can be obviously observed on stripper column plate,
And after production technology optimization, i.e., after change fatty acid zinc addition opportunity, in the case of running the same time, on stripper column plate then
Without apparent bur, production technology has better practical value and promotes and applies meaning after showing optimization.
Claims (4)
1. a kind of production method for improving Corvic thermal stability, which is characterized in that this method specifically includes following step
It is rapid:
(1) after applying kettle, start main pan feeding program, buffer be first added, sequentially add pure water and vinyl chloride monomer, dispersing agent 1,
Dispersing agent 2, initiator；
(2) to which after reaction, fatty acid zinc is added with terminator after compounding with terminator and carries out termination reaction；Utilize discharging pump
Slurry in kettle is got in blow tank, then strips and is further dried by stripper；
When preparing Corvic SG5 type, each quality of material ratio is mono- 1 ︰ of Ti ︰ dispersing agent of Huan Chong Ji ︰ Chun Shui ︰ Lv Yi Xi
2 ︰ Yin Fa Ji ︰ Zhi fat Suan Xin ︰ terminator of dispersing agent=60 ︰, 31000 ︰, 25500 ︰, 285 ︰, 150 ︰, 90 ︰, 6 ︰ 40；
Or are as follows: mono- 1 ︰ dispersing agent of Ti ︰ dispersing agent, 2 ︰ Yin Fa Ji ︰ Zhi fat Suan Xin ︰ terminator=60 ︰ of Huan Chong Ji ︰ Chun Shui ︰ Lv Yi Xi
31000 ︰, 25500 ︰, 285 ︰, 150 ︰, 90 ︰, 7 ︰ 40；
Or are as follows: each quality of material ratio is mono- 1 ︰ dispersing agent of Ti ︰ dispersing agent, the 2 ︰ Yin Fa Ji ︰ rouge of Huan Chong Ji ︰ Chun Shui ︰ Lv Yi Xi
Fat Suan Xin ︰ terminator=60 ︰, 31000 ︰, 25500 ︰, 285 ︰, 150 ︰, 90 ︰, 8 ︰ 40；
The dispersing agent 1 is the mixture that total mass concentration is 6.4 ~ 6.9%；Specifically include polyvinyl alcohol L-10, LW-100,
Hydroxypropyl methyl cellulose 65HD50；Each quality of material ratio is polyvinyl alcohol L-10 ︰ LW-100 ︰ hydroxypropyl methyl cellulose
1 ︰ 1 of the ︰ of 65HD50=5.9, wherein hydroxypropyl methyl cellulose 65HD50 is only in terms of butt；
The dispersing agent 2 is the polyvinyl alcohol GH-20 that mass concentration is 3.9 ~ 4.2%.
2. improving the production method of Corvic thermal stability as described in claim 1, which is characterized in that the buffer
The ammonium bicarbonate aqueous solution for being 9 ~ 11% for mass concentration.
3. improving the production method of Corvic thermal stability as described in claim 1, which is characterized in that the initiator
The mixture for being 11 ~ 13% for total mass concentration；Specifically include dicetyl peroxydicarbonate two ester and peroxidating neodecanoic acid isopropylbenzene
Ester；By quality ratio, two cumyl peroxyneodecanoate=2 Yi Zhi ︰ of dicetyl peroxydicarbonate~3 ︰ 1.
4. improving the production method of Corvic thermal stability as described in claim 1, which is characterized in that the fatty acid
Zinc is the fatty acid zinc that Zn content is greater than 5.5%.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101735373A (en) * | 2009-12-18 | 2010-06-16 | 昊华宇航化工有限责任公司 | New process for SG3 type PVC (polyvinyl chloride) resin production |
| CN101921354A (en) * | 2009-06-16 | 2010-12-22 | 中国石油化工股份有限公司 | Preparation method of high transparent polyvinyl chloride resin |
| CN102952220A (en) * | 2011-08-30 | 2013-03-06 | 中国石油化工股份有限公司 | Preparation method of polyvinyl chloride spherical resin |
| CN102977241A (en) * | 2012-12-07 | 2013-03-20 | 青岛鑫万通塑业发展有限公司 | Method for enhancing impact resistance of PVC (polyvinyl chloride) by using metallic stearate |
-
2015
- 2015-12-08 CN CN201510892801.8A patent/CN105294895B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101921354A (en) * | 2009-06-16 | 2010-12-22 | 中国石油化工股份有限公司 | Preparation method of high transparent polyvinyl chloride resin |
| CN101735373A (en) * | 2009-12-18 | 2010-06-16 | 昊华宇航化工有限责任公司 | New process for SG3 type PVC (polyvinyl chloride) resin production |
| CN102952220A (en) * | 2011-08-30 | 2013-03-06 | 中国石油化工股份有限公司 | Preparation method of polyvinyl chloride spherical resin |
| CN102977241A (en) * | 2012-12-07 | 2013-03-20 | 青岛鑫万通塑业发展有限公司 | Method for enhancing impact resistance of PVC (polyvinyl chloride) by using metallic stearate |
Non-Patent Citations (1)
| Title |
|---|
| 脂肪酸锌在氯乙烯聚合中的应用;张为民;《中国氯碱》;19950615;第30-31页 |
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