CA1230213A - Process for the manufacture of polypropylene fibres - Google Patents
Process for the manufacture of polypropylene fibresInfo
- Publication number
- CA1230213A CA1230213A CA000459322A CA459322A CA1230213A CA 1230213 A CA1230213 A CA 1230213A CA 000459322 A CA000459322 A CA 000459322A CA 459322 A CA459322 A CA 459322A CA 1230213 A CA1230213 A CA 1230213A
- Authority
- CA
- Canada
- Prior art keywords
- polypropylene
- extrusion
- fires
- manufacture
- stretching
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
- D01F6/02—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D01F6/04—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyolefins
- D01F6/06—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolymers obtained by reactions only involving carbon-to-carbon unsaturated bonds from polyolefins from polypropylene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/34—Heterocyclic compounds having nitrogen in the ring
- C08K5/3467—Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
- C08K5/3477—Six-membered rings
- C08K5/3492—Triazines
- C08K5/34924—Triazines containing cyanurate groups; Tautomers thereof
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Health & Medical Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Artificial Filaments (AREA)
Abstract
Abstract of disclosure Disclosed is a process for the manufacture of polypropylene fibres having improved stretching properties.
The process consists in introducing from about 0.01 to about 0.5% by weight, based on polypropylene of tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate into the polypropylene and in carrying out the extrusion of the polypropylene at a temperature comprised between about 220°C and 280°C.
The process consists in introducing from about 0.01 to about 0.5% by weight, based on polypropylene of tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate into the polypropylene and in carrying out the extrusion of the polypropylene at a temperature comprised between about 220°C and 280°C.
Description
. '17~302~L3 PROCESS FOR THE MANUFACTURE OF POLYPROPYLENE FIRES
_ The present invention relates to a process for the manufacture of polypropylene fires having stretching properties at the outlet of the die, greatly improved as regards to what is presently known in the art.
It is well-known that the polypropylene fires have many applications for several years, for instance non-woven fabric, carpets and other analogs.
In the usual processes for the manufacture of fires, polypropylene is introduced in the melting stave in a sheet die having a high number of orifices, generally between 2û00 and about 20,0D0. Polypropylene is introduced into such a die in order to give it the form of a yarn. These yarns are then stretched continuously in an horizontal oven at a temperature comprised between 90 and 16DC. The stretching rates which are normally used are usually comprised between 100 and 300%. It is also known in the art that a low stretching rate will produce a fire having a high residual elongation, but such a property leads to introduce in the horizontal oven a yarn having a finer diameter in order to obtain the desired number of denier. Therefore a more important stretching of the material must be applied at the outlet of the sheet die.
The stretching properties of the yarns crossing these orifices depend particularly on the nature of the polypropylene yarn in the melting stave, and particularly on the dispersion of the molecular weight of this latter.
Moreover, the fires may be stretched upward or downward, in accordance with the selected process, or still in accordance with the selected melt spinning speed, the highest speeds being reached with downward stretching.
Presently, the polypropylene which are used in the manufacture of fires do not present a sufficient elongation Al viscosity, that is to say, a viscosity such that it is possible to form a yarn with the melt material at a high speed, and such that it allows to suitably stretch this yarn in order to obtain fires of 1.5 denier, in case of a upward stretching at a speed of about ~Om/minute.
,~"};
~23~2~3
_ The present invention relates to a process for the manufacture of polypropylene fires having stretching properties at the outlet of the die, greatly improved as regards to what is presently known in the art.
It is well-known that the polypropylene fires have many applications for several years, for instance non-woven fabric, carpets and other analogs.
In the usual processes for the manufacture of fires, polypropylene is introduced in the melting stave in a sheet die having a high number of orifices, generally between 2û00 and about 20,0D0. Polypropylene is introduced into such a die in order to give it the form of a yarn. These yarns are then stretched continuously in an horizontal oven at a temperature comprised between 90 and 16DC. The stretching rates which are normally used are usually comprised between 100 and 300%. It is also known in the art that a low stretching rate will produce a fire having a high residual elongation, but such a property leads to introduce in the horizontal oven a yarn having a finer diameter in order to obtain the desired number of denier. Therefore a more important stretching of the material must be applied at the outlet of the sheet die.
The stretching properties of the yarns crossing these orifices depend particularly on the nature of the polypropylene yarn in the melting stave, and particularly on the dispersion of the molecular weight of this latter.
Moreover, the fires may be stretched upward or downward, in accordance with the selected process, or still in accordance with the selected melt spinning speed, the highest speeds being reached with downward stretching.
Presently, the polypropylene which are used in the manufacture of fires do not present a sufficient elongation Al viscosity, that is to say, a viscosity such that it is possible to form a yarn with the melt material at a high speed, and such that it allows to suitably stretch this yarn in order to obtain fires of 1.5 denier, in case of a upward stretching at a speed of about ~Om/minute.
,~"};
~23~2~3
2.
.~:
In case of a downward stretching, the usual polypropylene do not allow to reach high melt spinning speeds of about mounts loin order to overcome these drawbacks, it has already been proposed to introduce peroxides in polypropylene compositions. However, this process did not lead to favorable results in case of upward stretching, because the viscosity of the composition was too low to have a chance to form a yarn. Moreover the material which contains these peroxides is partially degraded, typically it has a high melt flow index and a very low viscosity, these facts being not always very interesting for some fur-then applications.
There is therefore a need for a process for the manufacture of polyp propylene fires having improved stretching properties.
The first object of the invention is to overcome all these here above mentioned drawbacks.
An object of the present invention is a process for the manufacture of polypropylene fires which allows an easy extrusion of the yarns either upward or downward, while obtaining fires having an acceptable residual elongation.
A particular object of the present invention is a process for the manufacture of polypropylene fires having low denier, generally comprised between 5 and 1 denier.
The process of the present invention for the manufacture of polyp propylene fires having improved stretching properties comprises the steps which consist in introducing into polypropylene, from about 0.01 to about 0.5% by weight, based on polypropylene, of iris t3,5-di-t-butyl-4-hydroxy-benzyl)isocyanurate, and in carrying out the extrusion at a temperature comprised between 220C and awoke.
The polypropylene which is used in the process of the invention is a propylene crystalline homopolymer, which may eventually contain nucleating agents. Said crystalline polypropylene is generally obtained by polymerize-lion in the presence of a stereo specific catalyst.
It has unexpectedly been noticed that if 1,3,5-triazine-2,4,G-t1H,3H.
triune, - 1,3,5 - iris -3,5 - bus t1.1-dimethylethyl)-4-hydroxyphenyl-methyl, more commonly called tris(3,5-di-t-butyl-4-hydrDxy 3-isocyanu-rate, is introduced in an amount from n.01 to 0,5% by weight, based on the polypropylene weight, the elongation Al viscosity properties of the polymer are greatly improved, the stretching of the extruded yarns being carried out either upward or downward.
.~:
In case of a downward stretching, the usual polypropylene do not allow to reach high melt spinning speeds of about mounts loin order to overcome these drawbacks, it has already been proposed to introduce peroxides in polypropylene compositions. However, this process did not lead to favorable results in case of upward stretching, because the viscosity of the composition was too low to have a chance to form a yarn. Moreover the material which contains these peroxides is partially degraded, typically it has a high melt flow index and a very low viscosity, these facts being not always very interesting for some fur-then applications.
There is therefore a need for a process for the manufacture of polyp propylene fires having improved stretching properties.
The first object of the invention is to overcome all these here above mentioned drawbacks.
An object of the present invention is a process for the manufacture of polypropylene fires which allows an easy extrusion of the yarns either upward or downward, while obtaining fires having an acceptable residual elongation.
A particular object of the present invention is a process for the manufacture of polypropylene fires having low denier, generally comprised between 5 and 1 denier.
The process of the present invention for the manufacture of polyp propylene fires having improved stretching properties comprises the steps which consist in introducing into polypropylene, from about 0.01 to about 0.5% by weight, based on polypropylene, of iris t3,5-di-t-butyl-4-hydroxy-benzyl)isocyanurate, and in carrying out the extrusion at a temperature comprised between 220C and awoke.
The polypropylene which is used in the process of the invention is a propylene crystalline homopolymer, which may eventually contain nucleating agents. Said crystalline polypropylene is generally obtained by polymerize-lion in the presence of a stereo specific catalyst.
It has unexpectedly been noticed that if 1,3,5-triazine-2,4,G-t1H,3H.
triune, - 1,3,5 - iris -3,5 - bus t1.1-dimethylethyl)-4-hydroxyphenyl-methyl, more commonly called tris(3,5-di-t-butyl-4-hydrDxy 3-isocyanu-rate, is introduced in an amount from n.01 to 0,5% by weight, based on the polypropylene weight, the elongation Al viscosity properties of the polymer are greatly improved, the stretching of the extruded yarns being carried out either upward or downward.
3 ~X3~2~3 However, it has been noted that the best results were obtained when said compound was used in an amount comprised between about û.05 and 0.2%
by weight.
When amounts lower than 0.01% by weight are used, based on pulpier-pylon, no significant effect is noted: on the other hand, the use of amounts higher than 0.5~ by weight do not bring any additional benefit.
When the stretching of the extruded yarns have been carried out upwards, we reached to form fire of 3 deniers having a residual elongation as high as 25D%, and fires of 1.5 denier still having an elongation of 100%.
This fact it quite unexpected, if it is taken into account that this result is obtained with orifices of the extrusion die having a L/D ratio of Z, because with usual compositions, extruded on the same sheet dies, thus having the same L/D ratio, many breaks of the yarn are obtained at such a stretching.
Although we are not bound by the proposed theory, it may however be supposed that the introduction of a compound such as trist3,5-di-t-butyl-4-hydroxybenzyl~isocyanurate has an influence on the dispersion of the mole-cuter weight of the polypropylene. Moreover, this compound allows to control said dispersion by means of the temperature at which the polymer material, which has to be treated, is introduced into the sheet die.
It has been noted that the process of the invention may be carried out successfully if the polymer material is extruded in the sheet die at a temperature comprised between about 220 and about 2B0C. More part-ocularly, when the yarns are stretched upwards, the extrusion is carried out at a temperature comprised between about 220 and about 250C, and preferably between about 230 and about 25GC, while when the yarns are stretched downwards, the extrusion is carried out at a temperature comprised between about 220 and about 280C, and preferably between about 230C and 260C.
The low temperatures are generally used to manufacture fires of high denier.
The following examples are given in order to better illustrate the process of the present invention, but without limiting its scope.
Example 1 0.15 parts by weight of iris t3,5-di-t-butyl-4-hydroxyben~yl)isocyanu-rate were introduced into 100 parts by weight of propylene homopolymer having a melt flow index of US g~10 mix determined at 230C under a pressure
by weight.
When amounts lower than 0.01% by weight are used, based on pulpier-pylon, no significant effect is noted: on the other hand, the use of amounts higher than 0.5~ by weight do not bring any additional benefit.
When the stretching of the extruded yarns have been carried out upwards, we reached to form fire of 3 deniers having a residual elongation as high as 25D%, and fires of 1.5 denier still having an elongation of 100%.
This fact it quite unexpected, if it is taken into account that this result is obtained with orifices of the extrusion die having a L/D ratio of Z, because with usual compositions, extruded on the same sheet dies, thus having the same L/D ratio, many breaks of the yarn are obtained at such a stretching.
Although we are not bound by the proposed theory, it may however be supposed that the introduction of a compound such as trist3,5-di-t-butyl-4-hydroxybenzyl~isocyanurate has an influence on the dispersion of the mole-cuter weight of the polypropylene. Moreover, this compound allows to control said dispersion by means of the temperature at which the polymer material, which has to be treated, is introduced into the sheet die.
It has been noted that the process of the invention may be carried out successfully if the polymer material is extruded in the sheet die at a temperature comprised between about 220 and about 2B0C. More part-ocularly, when the yarns are stretched upwards, the extrusion is carried out at a temperature comprised between about 220 and about 250C, and preferably between about 230 and about 25GC, while when the yarns are stretched downwards, the extrusion is carried out at a temperature comprised between about 220 and about 280C, and preferably between about 230C and 260C.
The low temperatures are generally used to manufacture fires of high denier.
The following examples are given in order to better illustrate the process of the present invention, but without limiting its scope.
Example 1 0.15 parts by weight of iris t3,5-di-t-butyl-4-hydroxyben~yl)isocyanu-rate were introduced into 100 parts by weight of propylene homopolymer having a melt flow index of US g~10 mix determined at 230C under a pressure
4. lo Lo of 2.16 kg in accordance with the ASTM D 1Z3~ method.
The resulting blend was introduced into an extrusion sheet die at a temperature of 23DC. The finest fires which have been obtained, had 3 deniers, with an upward stretching, at a speed of 50 minute: the fires had a residual elongation of ODD%. The L/D ratio of the orifices of the sheet of the die was 2.
By way of comparison, polypropylene containing D.D5% of a usual peroxide, was extruded. With said polypropylene it has never been possible, by means of an upward stretching, to obtain fires of 3 deniers.
Example 2 D.05 parts by weight of iris (3,5-di-t-butyl-4-hydroxybenzyl~isocya-curate were introduced into ODD parts by weight of the polypropylene used in Example 1.
The resulting blend was thereafter introduced into an extrusion sheet die at a temperature of 25DC.
Fires of 3 deniers have been manufactured by upward stretching, at a speed of Monet These fires had a residual elongation of 250%.
Fires of 1.5 denier having a residual elongation of ODD%
In the present example, it has been possible to manufacture finer yarns at the end of the sheet die, that allow to use lower stretching rates during the passage in the horizontal oven.
Thy L/D ratio of the orifice of the sheet of the die was 2. It has also been observed 1 break/hour with the sheet die which has been employed.
This sheet die had 1~D,000 orifices.
Example 3 The same blend as defined in Example 2 was prepared. This blend was thereafter extruded at a temperature of 260C in an extrusion sheet die working with a downward stretching.
Fires of 1.5 denier were manufactured with a melt spinning speed of about Monet The number of breaks per hour had never exceed 3 with the sheet die employed.
This sheet die had 12,000 orifices.
I
The resulting blend was introduced into an extrusion sheet die at a temperature of 23DC. The finest fires which have been obtained, had 3 deniers, with an upward stretching, at a speed of 50 minute: the fires had a residual elongation of ODD%. The L/D ratio of the orifices of the sheet of the die was 2.
By way of comparison, polypropylene containing D.D5% of a usual peroxide, was extruded. With said polypropylene it has never been possible, by means of an upward stretching, to obtain fires of 3 deniers.
Example 2 D.05 parts by weight of iris (3,5-di-t-butyl-4-hydroxybenzyl~isocya-curate were introduced into ODD parts by weight of the polypropylene used in Example 1.
The resulting blend was thereafter introduced into an extrusion sheet die at a temperature of 25DC.
Fires of 3 deniers have been manufactured by upward stretching, at a speed of Monet These fires had a residual elongation of 250%.
Fires of 1.5 denier having a residual elongation of ODD%
In the present example, it has been possible to manufacture finer yarns at the end of the sheet die, that allow to use lower stretching rates during the passage in the horizontal oven.
Thy L/D ratio of the orifice of the sheet of the die was 2. It has also been observed 1 break/hour with the sheet die which has been employed.
This sheet die had 1~D,000 orifices.
Example 3 The same blend as defined in Example 2 was prepared. This blend was thereafter extruded at a temperature of 260C in an extrusion sheet die working with a downward stretching.
Fires of 1.5 denier were manufactured with a melt spinning speed of about Monet The number of breaks per hour had never exceed 3 with the sheet die employed.
This sheet die had 12,000 orifices.
I
Claims (6)
What we claim is :
1) Process for the manufacture of polypropylene fibres having improved stretching properties, which comprises the step which consist in intro-ducing into polypropylene, from about 0.01 to about 0.5% by weight, based on the polypropylene weight, of tris[3,5-di-t-butyl-4-hydroxybenzyl) iso-cyanurate and in carrying out the extrusion of polypropylene at a tempe-rature comprised between about 220 end about 280°C.
2) Process according to claim 1 wherein an amount comprised between about 0.05 and 0.2% by weight, based on polypropylene, of tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate is introduced into polypropylene.
3) Process according to claim 1 wherein the extrusion is carried out at a temperature comprised between about 220 and 250°C when an upward stret-ching is carried out.
4) Process according to claim 3 wherein the extrusion is carried out at a temperature comprised between about 230° and 250°C.
5) Process according to claim 1 wherein the extrusion is carried out at a temperature comprised between about 220°C and about 260°C when a down-ward stretching is carried out.
6) Process according to claim 5 wherein the extrusion is carried out at a temperature comprised between 230° and 260°C.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| LU84944A LU84944A1 (en) | 1983-08-02 | 1983-08-02 | PROCESS FOR PRODUCING POLYPROPYLENE FIBERS |
| LU84944 | 1983-08-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1230213A true CA1230213A (en) | 1987-12-15 |
Family
ID=19730129
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000459322A Expired CA1230213A (en) | 1983-08-02 | 1984-07-20 | Process for the manufacture of polypropylene fibres |
Country Status (10)
| Country | Link |
|---|---|
| BE (1) | BE900217A (en) |
| CA (1) | CA1230213A (en) |
| CH (1) | CH661274A5 (en) |
| DE (1) | DE3428068C2 (en) |
| DK (1) | DK164513C (en) |
| FR (1) | FR2550231B1 (en) |
| GB (1) | GB2144367B (en) |
| IT (1) | IT1180213B (en) |
| LU (1) | LU84944A1 (en) |
| NL (1) | NL192834C (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3531483A (en) * | 1968-10-25 | 1970-09-29 | Goodrich Co B F | Hydroxyphenylalkyleneyl isocyanurates |
| GB1380449A (en) * | 1972-05-12 | 1975-01-15 | Ici Ltd | Polypropylene composition |
| NZ186352A (en) * | 1977-02-07 | 1979-06-08 | Ici Ltd | Propylene polymer containing isocyanurate anti oxidant |
| US4185004A (en) * | 1977-04-27 | 1980-01-22 | Phillips Petroleum Company | Multi-component stabilizing system for pigmented polyolefins |
| FR2393829A1 (en) * | 1977-06-07 | 1979-01-05 | Solvay | PROCESS FOR THE EXTRUSION OF COMPOSITIONS BASED ON ALPHA-OLEFIN POLYMERS |
-
1983
- 1983-08-02 LU LU84944A patent/LU84944A1/en unknown
-
1984
- 1984-07-16 CH CH3446/84A patent/CH661274A5/en not_active IP Right Cessation
- 1984-07-18 GB GB08418245A patent/GB2144367B/en not_active Expired
- 1984-07-20 CA CA000459322A patent/CA1230213A/en not_active Expired
- 1984-07-25 BE BE0/213375A patent/BE900217A/en not_active IP Right Cessation
- 1984-07-30 DE DE3428068A patent/DE3428068C2/en not_active Expired - Fee Related
- 1984-07-31 DK DK371184A patent/DK164513C/en not_active IP Right Cessation
- 1984-08-01 NL NL8402407A patent/NL192834C/en not_active IP Right Cessation
- 1984-08-02 FR FR8412244A patent/FR2550231B1/en not_active Expired
- 1984-08-02 IT IT22199/84A patent/IT1180213B/en active
Also Published As
| Publication number | Publication date |
|---|---|
| DE3428068A1 (en) | 1985-02-21 |
| GB2144367B (en) | 1986-11-05 |
| GB8418245D0 (en) | 1984-08-22 |
| GB2144367A (en) | 1985-03-06 |
| NL8402407A (en) | 1985-03-01 |
| LU84944A1 (en) | 1985-04-24 |
| BE900217A (en) | 1985-01-25 |
| NL192834C (en) | 1998-03-04 |
| CH661274A5 (en) | 1987-07-15 |
| NL192834B (en) | 1997-11-03 |
| IT1180213B (en) | 1987-09-23 |
| IT8422199A0 (en) | 1984-08-02 |
| DK371184D0 (en) | 1984-07-31 |
| DE3428068C2 (en) | 1993-09-30 |
| DK371184A (en) | 1985-02-03 |
| FR2550231A1 (en) | 1985-02-08 |
| FR2550231B1 (en) | 1987-06-05 |
| DK164513B (en) | 1992-07-06 |
| DK164513C (en) | 1993-08-02 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |