CN100562613C

CN100562613C - Low-shrink polypropylene ribbon-like fibre and manufacture method thereof

Info

Publication number: CN100562613C
Application number: CN 02824032
Authority: CN
Inventors: B·G·莫林; M·E·考恩; K·B·希金斯
Original assignee: Milliken and Co
Current assignee: Milliken and Co
Priority date: 2001-12-21
Filing date: 2002-12-02
Publication date: 2009-11-25
Anticipated expiration: 2022-12-02
Also published as: EP1468131A1; WO2003057956A1; AU2002359546A1; JP2005533932A; CN1599813A; BR0215059A

Abstract

Be provided at the improvement that prevents thermal contraction and wet contraction problem in the specific polypropylene ribbon fiber.This fiber cuts into them the ribbon-like fibre of extremely thin and flat (and having very high aspect ratio) then mainly by at first producing polypropylene film or pipe.This fiber (thereby initial stage film and/or pipe) need have some compound, and after the heat setting, they fast and effeciently provide hardness for the target polypropylene ribbon-like fibre.Usually, these compounds are included in and bear abundant heat and make initial stage granular polymer fusing and make after this stereospecific polymer cooling, make polymer crystals in the target polypropylene form any structure of nucleus.Do not use the target polypropylene of nucleator to compare with cooling period, these compounds must make polymer crystals form nucleus under higher temperature.According to this mode, " sclerosis " nucleator compound is that polypropylene crystal growth is provided as nuclear location.Firm cutting initial stage film and/or pipe, fiber is exposed in the sufficient heat with the growth lattice structure then, thereby fiber is remained on ideal position.Preferably " sclerosis " compound comprises the dibenzylidene sorbitol compound, and less preferred compound, for example (for example sodium 2,2 '-methylene-two-(4 for Sodium Benzoate, some sodium and lithium phosphate, 6-two-three-butyl phenyl) phosphate is also referred to as NA-11).The present invention also comprises the specific manufacture method of this ribbon-like fibre of the present invention and the fabric product of being made by this fiber.

Description

Low-shrink polypropylene ribbon-like fibre and manufacture method thereof

Technical field

The present invention relates in specific polypropylene ribbon fiber, prevent the improvement of thermal contraction and wet contraction problem.This fiber cuts into them the ribbon-like fibre of extremely thin and flat (and having very high aspect ratio) then mainly by at first producing polypropylene film or pipe.This fiber (thereby the film at initial stage and/or pipe) need have some compound, and after the heat setting, they fast and effeciently provide hardness for the target polypropylene ribbon-like fibre.Usually, these compounds have comprised and bearing after abundant heat makes initial stage granular polymer fusing and make this stereospecific polymer cooling, make polymer crystals in the target polypropylene form any structure of nucleus.Do not use the target polypropylene of nucleator to compare with cooling period, these compounds must make polymer crystals form nucleus under higher temperature.According to this mode, " sclerosis " nucleator compound is that polypropylene crystal growth is provided as nuclear location.After cutting initial stage film and/or the pipe, fiber is exposed in the sufficient heat with the growth lattice structure then, thereby fiber is remained on ideal position.Preferably " sclerosis " compound comprises the dibenzylidene sorbitol compound, and less preferred compound, for example (for example sodium 2,2 '-methylene-two-(4 for Sodium Benzoate, some sodium and lithium phosphate, 6-two-three-butyl phenyl) phosphate is also referred to as NA-11).The present invention also comprises the specific manufacture method of this ribbon-like fibre of the present invention and the fabric product of being made by this fiber.

Background technology

In order to strengthen product or stable dimensions, the polypropylene ribbon fiber is used in the various final uses such as carpet backing, ramie cotton fabric and other fabric.Unfortunately, mainly be because the ribbon-like fibre component utilizes the standard polypropylene ribbon-like fibre of using at present to be subjected to high relatively shrinkage factor.Heat, humidity and other environmental factor all cause the contraction possibility of ribbon-like fibre (and yarn of being made by ribbon-like fibre), cause the interior contraction residual effect of product itself thus.Therefore, though be desirably in, regrettably, shrink and cause distortion that final carpet product is very bad or uneven such as using this polypropylene fibre in the final use of carpet backing.Perhaps, as selection, can compensate the highly shrinkable of expectation with the production method that forms carpet (for example carpet square), but because the expectation of carpet itself is shunk, can cause producing waste material or cause losing relatively costly finished carpet quantity of material at least and all results of the shrinkage factor that causes embodying by the carpet backing fiber itself.And this ribbon-like fibre of making in the past and implementing is subjected to relative low TENSILE STRENGTH.For cotton fibriia (for example in roofing product, pitch strengthen or the like), these shrinkage factor problems also are very important, so that to target product comprehensive enhancing ability that offers the best, and make and strengthen product and keep smooth.(use) in the past and be to use more expensive polyester and polyamide, thisly problematicly highly shrink as solving, only alternative method of the ribbon-like fibre of low TENSILE STRENGTH as fibre fractionation for carpet backing and linen-cotton.

All the time, wish this polypropylene ribbon (high aspect ratio) fiber is used in (as mentioned above) in the various product, from clothes to the carpet backing (and carpet pile), arrive reinforced fiber or the like again.This polypropylene ribbon fiber shows fabulous strength characteristics, and when being subjected to some " destructiveness " chemicals, is not easy cracking or corrosion.Yet, although have outstanding like this, useful characteristic, and as the byproduct of oil plant, polypropylene enriches, and polypropylene makes relatively cheap and produces stablely, and these fibers do not bear in the product of relative higher temperature when but being widely used in use, cleaning etc.This mainly is because aforementioned height and common thermal contraction heterogeneous and the wet shrinkage character that typical polypropylene ribbon fiber is showed.These fibers are not heat-staple, and when normal temperature (for example 150 ℃ and 130 ℃), shrinkage factor changes to 3-4% (being exposed in the hot-air) from about 2% (boiling water), change to 5-6% (for the hot-air of high temperature more) again.Shrinkage factor therefore high like this and that change causes the utilization of very desirable polypropylene fibre and handlability very low, especially for the heat-staple final use of needs (for example carpet pile, carpet backing, moulded parts or the like).

Past uses the polypropylene ribbon fiber to cause needs to estimate the non-homogeneous shrinkage factor of final products in carpet backing, therefore expects this manufacturing basically and/or further loses a certain amount of product during the processing.For example, the DIMENSIONAL STABILITY in order to print, the fiber component of at first will clustering adheres to after its carpet master backing parts, if this step is to wish to produce multicolour pattern or whole evenly color to the target substrate that clusters.After the printing, need drying steps suitably to make the color setting on the position, and reduce the potential bleeding between the color.The temperature that this print steps needs (for example 130 ℃ and more than) produces in being typically connected to the thermal treatment zone of printing equipment.Under such high temperature, the backing that comprises typical polypropylene ribbon fiber shows aforesaid high shrinkage (for example on average between 2-4%).Regrettably, this shrinkage factor is also controlled the dimensions of the substrate that clusters of red ink paste used for seals, has therefore determined the final size of entire product before adhering to time backing.So this time backing is cut into and the parts of expecting that cluster/relevant size of main backed product size usually.The heterogeneity of shrinkage factor, and need provide and the inferior backing of master unit with the parts different size that clusters, meaning needs the carpet of low-shrink polypropylene ribbon-like fibre master backing.Because its contractility is zero substantially, so select inferior backing even, appropriate size will obviously help to reduce the waste and the loss of making in this carpet reliably.

If do not wish printing, still there are fabric backed relevant potential problems with the high ribbon-like fibre master of contraction, promptly this situation needs emulsion binder that remaining time backing parts (and other parts) are bonded to the substrate that clusters/main backed product exactly.Also need dry to realize the quick setting of this adhesive.After exposing in sufficiently high temperature, contraction to a certain degree will appear in the main backing that includes interlayer polypropylene ribbon fiber, cause the bending (or with this carpet product in the relevant other problem of different size assembly) of final products thus potentially.

The simple solution that does not have these problems so far provides essence and this high identical TENSILE STRENGTH of ribbon-like fibre performance of shrinking at least.Be used to improve some ideas of non-banded polypropylene fibre shrink characteristics, comprise the molecular weight distribution of dwindling and controlling polypropylene composition itself in the every fiber, or heat setting before and during the machining target fibers.Regrettably, at first molecular weight control is extremely difficult realizes, and above-named shrinkage factor (for the various application in the textile industry, these shrinkage factors are also too high) can only be provided.And, as a rule, use very high heat-set temperature to cause the excellent handle forfeiture of processed fiber during the mechanical treatment.Another solution of this problem is pre-high shrinkage, and it is included on the compressible paper web and twines fiber, makes fiber be arranged in stove and long-time the contraction, and (with the paper web compression) is wrapped in again then on the qualified tube and is used for further processing.Produce qualified yarn, this handles relatively more expensive, finished fiber is compared with nylon fiber with polyester do not had competitiveness.Therefore, in relevant prior art, there are not any explanation and the open improvement of the polypropylene fibre technology having been carried out any thermal contraction and/or wet contraction.In addition, have been found that these limited shrinkage factor improvement programs that are used for non-ribbon-like fibre can not be used for ribbon-like fibre, so that the benefit of any essence low-shrinkage to be provided.

As mentioned above, the present invention relates generally to the manufacturing of low-shrink polypropylene ribbon-like fibre.For purpose of the present invention, term " ribbon-like fibre " or fiber are intended to the monfil that comprises that aspect ratio was at least 2: 1, are wide and flat relatively fibers therefore.As mentioned above, this ribbon-like fibre is generally by beginning to produce polypropylene film and/or pipe is produced, from wherein cutting desirable fiber (thus, according to the flat specification of ideal, by using this cutting process such as the cutting equipment of cutting knife, for target fibers itself provides basic aspect ratio uniformly, during actual cutting process, cutting equipment is in proportional spacing each other basically).

Summary of the invention

Therefore the objective of the invention is to provide the shrinkage factor of improvement for the polypropylene ribbon fiber, and its TENSILE STRENGTH of not obvious reduction.Another object of the present invention provides a series of additives, and in the finite concentration scope, this additive will provide low-shrinkage and/or high-tensile strength grade more for the ribbon-like fibre of the present invention yarn of its manufacturing (and by).Another purpose of the present invention provides a kind of carpet that has the polypropylene backing, and this polypropylene backing shows very low percent thermal shrinkage.Another object of the present invention provides a kind of particular method of manufacture that comprises the polypropylene ribbon fiber of nucleator, and this polypropylene ribbon fiber is allowed with its final fabric of making this low contraction, high-tensile strength.A further object of the present invention provides a kind of carpet product that has backing, and this backing mainly is made up of polypropylene fibre relatively cheap and that show low-down shrinkage factor.

Therefore, the present invention includes a kind of polypropylene ribbon fiber, it comprises the nucleator compound of 10ppm at least, and shows the TENSILE STRENGTH of at least 3 gram/DENIER.The present invention also comprises a kind of polypropylene ribbon fiber, and it comprises the nucleator compound of 10ppm at least, and is exposed to the shrinkage factor that shows after 150 ℃ of hot-airs at the most 2%, and wherein said fiber also shows the TENSILE STRENGTH of at least 2.5 gram/DENIER.Equally, the present invention includes a kind of polypropylene ribbon fiber, the scattering peak value center of the X ray scattering pattern that it shows is at the most at 0.4 degree.Some yarn and the fabric product that comprise fiber of the present invention are also included within the present invention.Relate in particular to a kind of carpet product that comprises end face and bottom surface, the fibrous substrate of fiber, satin face fabric fibre or same type of wherein clustering bonds to described end face, the backing that mainly comprises polypropylene fibre bonds to described bottom surface, and wherein said fiber comprises the nucleator compound of 10ppm at least.Preferably, under the situation same as described above, this carpet product shows very low shrinkage factor.

And, the present invention also relates to a kind of method of making this fiber, comprise following sequential steps: a) polypropylene formulations with heating is squeezed into film or tubulose, this polypropylene comprises the nucleator compound of about 2000ppm at the most, be preferably about at the most 1500ppm, more preferably about at the most 1000ppm most preferably is below about 800ppm; B) immediately the film or the pipe of step " a " is quenched into a certain temperature, this temperature prevents the polypropylene crystal orientation in film or the pipe; C) be used in the cutting equipment of vertically arranging along described film or pipe and cut described film or pipe, thereby therefrom produce independent ribbon-like fibre; D) with at least 5: the described independent ribbon-like fibre of 1 draw ratio mechanical stretching, simultaneously described fiber is exposed under the temperature between 250 and 360, this temperature is preferably between 260 °F and 330 °F, most preferably be between 270 °F and 300 °F, allow the polypropylene crystal orientation in the fiber thus.Preferably, step " b " at the most 95 ℃ and at least about 5 ℃ temperature under carry out, preferably, between 5 ℃ and 60 ℃, most preferably, between 10 ℃ and 40 ℃ (perhaps, only by making bath itself adapt to the environment of about 25-30 ℃ temperature, and allow liquid) as far as possible near room temperature.In addition, this temperature need guarantee that the crystal orientation does not appear in component polymer (being polypropylene, and may being for example polyethylene etc. of other polymers compositions that they can obviously not influence its shrinkage character as wherein structure enhancement additive).Realize this orientation after the hot-stretch step, determined that now this orientation carries out the sclerosis that needs to the target ribbon-like fibre, therefore increased the intensity and the modulus of this fiber.The ratio of draw speed and linear velocity should surpass at least five times to the ratio of cutting equipment translational speed of draw speed and film.Preferably, this draw speed is a 400-700 feet per minute clock, and the speed of film before cutting equipment is about 50-400 feet per minute clock, and the ratio of the draw speed between these two districts was from about 3: 1 to about 10: 1, as method for optimizing itself, will discuss in more detail below.After extruding and the stretching, last heat-set temperature need be with polypropylene crystalline structure " locking " in position.This heat setting step continued usually less than 1 second, may reach a few minutes (for example, from about 1/10 second, preferred about 1/2 second, up to about 3 minutes, being preferably greater than 1/2 second).Heat-set temperature must suitably surpass draft temperature, must be at least 265 °F, more preferably, is at least about 290 °F, most preferably, is at least about 300 °F (and up to 380 °F).Term " mechanical stretching " is intended to comprise many programs, and they mainly comprise and tensile force being applied on the fiber so that stretch wherein polymer.This program can use many devices to finish, and comprises godet roller, mip rolls, steam generator, heat or cold jet plane (air or steam) and other similar machinery, but is not limited to them.

Single fiber by extruding high aspect ratio and sufficient size also can be made this banded yarn, then carries out stretching and the heat setting step thus, so that obtain this low-shrinkage characteristic.When discussing all shrinkage factor values that are fit to fiber of the present invention and manufacture method thereof, for every kind of test (hot-air and boiling water), their corresponding open-assembly times are about 5 minutes.As mentioned above, in about 150 ℃ hot-air, the percent thermal shrinkage of fiber of the present invention is at most 2.0%; Preferably, this percent thermal shrinkage is at most 1%; More preferably at the most 0.5%; Most preferably be at the most 0.1%.Equally, the intrastitial nucleation dosage of the present invention is at least 10ppm; Preferably, this amount is at least 50ppm; Most preferably be 100ppm at least, be about 700-800ppm up to preferred maximum (in order to keep TENSILE STRENGTH).After the fiber itself heat setting, any amount in this scope should enough provide desirable shrinkage factor; Yet,, should avoid excessive (for example surpassing about 2000ppm) mainly due to cost and TENSILE STRENGTH problem.

Yet, carry out very fast fiber manufacturing if carry out very high processing speed (for example, incipient extension speed or heat setting draw speed), in order under this high draw speed, to provide crystallization rate faster, may need more substantial nucleator compound, for example reach about 2000ppm.

And, determine now, the content that is combined in the nucleator compound in the polypropylene fibre in the carpet master backing (or inferior backing) is between 10ppm and 1000ppm the time, provide very ideal results, i.e. backing and the substrate that clusters/backing synthetic or even the not obvious contraction of whole carpet product.Therefore, comprise that any low contraction carpet backing that major part contains the polypropylene fibre of this nucleator compound (necessary amounts is preferably between 200ppm and the 800ppm, most preferably is between 400ppm and the 700ppm) provides the low-shrinkage characteristic that needs.Ribbon-like fibre of the present invention and/or yarn, and the fiber of polypropylene raw material, multifilament and monofilament-type and/or yarn can be used for this improved, the low carpet product that shrinks.

Term " polypropylene " is intended to comprise any polymers compositions of propylene monomer, it comprise single or mix or freely select with other and the copolymer of polyolefin, alkadienes or other monomer (for example ethene, butylene etc.) of orientation.This term also comprises the compositing monomer (for example syndiotaxy, isotaxy etc.) of any different structure and arrangement.Therefore, the term that is applied to fiber is intended to comprise actual long wire, band shape, strained polymer such as thread.Polypropylene can be any standard melt stream (by test); Yet the melt flow index of the acrylic resin of standard fibers grade (Melt Flow Indices) scope is maintained at about between 2 and 50.Opposite with (for example, being instructed in people's such as Hamada the U.S. Pat 4016118) such as standard plaque, container, thin plates, fibre structure is obviously different, because the length that they show is considerably beyond its cross section (for example, the diameter of cylindrical fibre).Fiber is to form by extruding and stretching; Object is to form through blowing mould and injection molding, is called as two kinds of different manufacture methods.In addition, intrastitial crystalling propylene form also is different from standard object, plaque, thin plate etc.For example, the dpf of this polypropylene fibre about at the most 5000; Yet the dpf of these other objects is much bigger.The polypropylene object shows spherulite usually, and fiber shows as crystal structure elongated, that elongate.Therefore, there is very big-difference in the structure between fiber and the polypropylene object, so that any prediction that the polyacrylic spherolite of nucleation (crystal grain) is carried out can not provide any basis, is used for determining the effectiveness of this nucleator as the additive in the polypropylene fibre.

Term " nucleator (nucleators) ", " nucleator compound ", " nucleator (nucleatingagent) ", " nucleator (nucleaing agents) " are intended to comprise substantially any Polypropylene Additive alone or in combination, this additive is the transition from the polypropylene fusion state to the solid cooled structure, for polypropylene produces nucleation site.Therefore and since polypropylene miser (comprising the nucleator compound) must fusing so that itself is squeezed into fiber, so polypropylene is during just from the cooling of its molten condition, the nucleator compound just provides this nucleation site.This compound provides the sole mode of required nucleation site is whether this position formed before polypropylene itself crystallization again.Therefore, any compound that shows this beneficial effect and characteristic is included in this definition.More specifically, this nucleator compound comprises the dibenzylidene sorbitol type, it is including but not limited to dibenzylidene sorbitol (DBS), monomethyl dibenzylidene sorbitol, and for example 1,3:2, two (the p-methyl dibenzylidene) D-sorbites (p-MDBS) of 4-, dimethyl dibenzylidene sorbitol, for example 1,3:2,4-two (3,4-dimethyl dibenzylidene) D-sorbite (3,4-DMDBS); Such other compound is again including but not limited to Sodium Benzoate, NA-11 or the like.This nucleator concentration (all) in the target polypropylene fibers is at least 10ppm, is preferably 50ppm at least.Therefore, from about 10ppm to about 2000ppm, preferably, from about 50ppm to about 1500ppm, most preferably, from about 100ppm to about 800ppm.And, as mentioned above, the ribbon-like fibre that must mainly make this invention by the film or the pipe of cutting extruding.

Equally, need not to limit, it seems that the nucleator that reduces to shrink most is this nucleator that shows high relatively solubility in propylene with any concrete scientific theory.Therefore, diffluent compound for example 1,3:2, two (the p-methyl dibenzylidene) D-sorbites of 4-are for desirable polypropylene fibre provides minimum shrinkage factor.Think that in the present invention the DBS derivative compound is the nucleator that reduces contraction most, because this compound produces small crystalline size.Other nucleator for example NA-11 also provides the low shrinkage character of allowing to target polypropylene fibers, therefore regards them as nucleator compound additive possible in the present invention.Basically, the required choice criteria of this nucleator compound be granularity (low more easy more handle, mix and with the target resin-bonded), the dispersibility of particle in the target resin (provide the most effective become nuclear properties) and nucleation temperature (crystallization temperature for example, by being melt into the differential scanning calorimetry method of nuclear resin, for resin sample is determined crystallization temperature), this temperature is high more good more.

Determine that the nucleator compound (being essentially liquid during therefore processing stage that fiber is made) that shows good solubility in target melt polypropylene resin provides effectively low shrinkage character.Therefore, as if the low DBS compound (comprising DBS, p-MDBS) that replaces brings less production problem and low shrinkage character is provided in finished product polypropylene fibre itself.Though p-MDBS is preferred, yet can utilize above-mentioned any nucleator in the present invention, as long as satisfy X ray scatterometry value or shrink requirement by using such compound to realize hanging down.For the such low shrinkage character and the improvement of sensation, the facility or the cost of processing are provided, also can use these nucleator mixtures during the processing.

Except above-mentioned these compounds, for those purposes, Sodium Benzoate and NA-11 are well-known as the nucleator of standard polypropylene structure (for example aforesaid plaque, container, film, thin plate etc.), and show fabulous recrystallization temperature and very fast mould cycle.The dibenzylidene sorbitol type shows characteristic of the same type and fabulous transparency in these standard polypropylene structures (plaque, thin plate etc.).For the purposes of the present invention, have been found that as the nucleator compound in the target polypropylene fibers, the dibenzylidene sorbitol type is preferred.

Immediate prior art reference teaches is added the nucleator compound in the plain polypropylene component (in the U.S. Pat 4016118 of for example above reference).Yet some instruction is included in interior some the DBS compound that uses of qualifying part fiber in the multicomponent polypropylene fabric structure.For example, people's such as United States Patent (USP) Connor US5798167 and the US5811045 of Pike instruct the DBS compound are added in the polypropylene of fibers form; Yet openly and between the present invention there is significant difference in these.For example, two patents all need above-mentioned multicomponent fibre structure.Therefore, even have the DBS compound in some polypropylene fibre component of every type of fiber, but the shrinkage factor of each fibre fractionation is by other polypropylene fibre component control that is not benefited from nucleator.And,, in polypropylene fibre, do not have formation to cause the thin slice of long period (measuring) by small angle x-ray scattering (SAXS) greater than 20nm owing to carry out back heat setting step.In addition, these thin slices provide desirable, fiber innovation, higher thermal contraction.For example, the fact of no less important is, people such as Connor need the nonwoven polypropylene sheets of fabric, and it comprises the DBS additive that is positioned at around the polypropylene tissue layer, and interior tissue layer does not comprise nucleating agent additive.There is not the auxiliary inner layer of polypropylene of nucleating agent additive to determine the shrinkage factor of this structure.And, because low contraction is not these patentees' a purpose, so they do not make their yarn and fiber experience heat setting program, so that make the crystal fibre structure permanent set of yarn itself.

In addition, " Journal of Applied Polymer Science " the 62nd volume 1965-75 page or leaf (1996), people such as Spruiell have disclosed the nucleation rate that uses during 0.1% MDBS nucleator increases spinning, but are not to be used for ribbon-like fibre.Yet after crystallization and the drawing of fiber, people such as Spruiell do not make the nucleation fiber stand any heat, and this is essential for giving best shrinkage character, so their filament contraction rate is similar to the conventional polypropylene fibre that does not have nucleating agent additive.

The special concern of this discovery is at least: exist (as described herein) of nucleator provides high long period measured value for the crystal microchip of polypropylene itself in the heat setting polypropylene fibre, and this discovery has been confirmed as first importance in the low-shrink polypropylene fibers manufacturing of the present invention.Obtain best illustration by this discovery hereinafter:

Polymer under dynamic temperature and the pressure condition when melt carries out crystallization, sub-cooled at first, carry out crystallization then, crystallization rate depends on nucleation site quantity and polymer growth speed, and the hot-working and the machining that are stood when they cool off with polymer successively are relevant.In normal fiber stretching production line, these processes are complicated especially.Yet, use small angle x-ray scattering (SAXS) (SAXS) can measure the result of this complicated crystallization, the SAXS long period of measurement is represented the average crystallite temperature.(they are sheet polymer crystal to higher SAXS long period corresponding to thicker thin slice, feature is the semi-crystalline polymer as PP), and show that by the SAXS peak value compare with nucleation polypropylene ribbon fiber not, the SAXS peak value is centered on the lower angle of scattering.The crystallization temperature of average crystalline is high more, and the SAXS long period of measurement is thick more.Furtherly, high more SAXS long period is the feature of thermally-stabilised more crystal group.Have the macrocyclic crystal of shorter SAXS with " fusing " or lax, and compare, under lower temperature, be recrystallized into new, thicker crystal with having the macrocyclic crystal of higher SAXS.Have the macrocyclic crystal of higher SAXS and under higher temperature, keep stable, destroy the more heats of stable needs of crystal structure.

In polymer samples, have the macrocyclic fiber of higher SAXS and under higher temperature, keep stable such as the high orientation of fiber.Therefore, compare with the polymer samples with the macrocyclic high orientation of lower SAXS, keep lower for higher temperature contraction, contraction is the lax normal effect of polymer samples of high orientation.In the present invention, just as what obviously see from these measured values, nucleating additive uses to form fiber with heat treatment, the SAXS scattering peak value center that it shows is at the most at 0.4 degree, this is corresponding to thicker thin slice, and these thin slices are highly stable successively and reveal low-shrinkage for very high thermometer.

And, paint for the end user also can for this fiber other aesthetic is provided.Therefore, these fibers also can comprise such as the colouring agent of pigment and be used for fast light fixer.For this reason, it is desirable to utilize can be with visible color or the colored nucleator that passes to target fibers.Also can there be other additive, comprises that antistatic additive, shinny compound, fining agent, antioxidant, antiseptic (are preferably the money base ion-exchange compound, for example from Milliken﹠amp; The Company supply

Antiseptic), UV stabilizing agent, stuffing or the like.And any fabric that constitutes with fiber of the present invention can be braiding, knitting, non-braiding, inlay linen-cotton and their any combination, but is not limited to these.In addition, this fabric comprises the fiber that is different from polypropylene fibre of the present invention, comprises: natural fabric, for example cotton thread, wool, abaca, hemp, ramie etc.; Synthetic fiber, for example polyester, polyamide, poly-aromatic polyamides, other polyolefin (comprising non-low-shrink polypropylene), PLA etc.; Inorfil, for example glass, contain boron fibre etc.; And their any mixture, but be not limited to these.

As the final use of ribbon-like fibre of the present invention, being carpet master backing and comprising the carpet of this main back lining components of special concern.These are described hereinafter in more detail.

Description of drawings

Accompanying drawing combines and constitutes the part of specification with this specification, accompanying drawing illustrates the possible preferred embodiment of making low-shrink polypropylene fibers of the present invention, and is used for explaining principle of the present invention with specification, wherein:

Fig. 1 is a schematic diagram of making the possible method for optimizing of low-shrink polypropylene ribbon-like fibre.

Fig. 2 is the side view that comprises the preferred carpet product of fiber of the present invention in backing.

The specific embodiment

Fig. 1 has described the non-limiting preferable procedure of making low-shrink polypropylene ribbon-like fibre of the present invention.Whole fiber manufacturing installation 10 comprises and mixes house steward 11, is used for mixed melting polymer and additive (for example above-mentioned nucleator compound), and they flow into extruder 12 then.The polymer of extruding enters mould 16 through measuring pump 14 then, makes film 17 on mould 16.Film 17 enters quenching bath 18 immediately then, and quenching bath comprises for example water etc. of liquid, and its temperature is set at 5-95 ℃ (preferably being about room temperature here).Here the draw speed of film is by draw roll and

idler roller

20,22,24,26,28 controls, though this speed can be to about 200 feet per minute clocks from about 20 feet per minute clocks, as long as incipient extension speed is about 1/5 of hot-stretch speed in the down-stream at the most, this speed setting preferably is about 100 feet per minute clocks.For further processing, tangible polymer crystal orientation should not appear within it in quenching film 19.If desired, can select to use 30,31,32,33,34,35 pairs of films of sand milling roller to carry out matting.Quenching film 19 enters cutting area 36 then, and cutting area has a plurality of fixed cutting tools 38 that separate with any desired spacing.Preferably, the spacing of these cutting knifes 38 is determined by formula, this formula is that draw speed multiply by the last width of target fibers extraction of square root (therefore, be about 3mm if draw ratio is 5: 1 and last width, the measured value of cutting knife spacing should be about 6.7mm) again.Firm quenching film 19 is cut into fiber 40, these fibers just evenly passed a series of force feeds and

idler roller

42,43,44,45 before drawing in high temperature furnace 46, the temperature range of high temperature furnace 46 is set between about 280 and 350 °F, in this example, be about 310 °F, its speed is 5 times of incipient extension speed with mentioned above the same at least.The draw speed of this raising realizes that by a series of hot-stretch rollers 48,50 (temperature is about 360-400 separately) present crystal orientation fiber 54 passes through from it.Last idler roller 52 leads to the circle axle (not shown) that is used to twine finished product ribbon-like fibre 54.

Forward Fig. 2 then to, illustrated carpet product 110 of the present invention comprises pile layer 112 and foam or cushion course 118, and (cushion course can be the fabric such as felt, or such as the resin of compounds such as polyvinyl chloride; Preferably, it is a polyurethane foam), pile layer 112 comprises the tufting fiber 114 that clusters by the main back sheet or the substrate that clusters, the main back sheet or the substrate that clusters comprise fiber 113 of the present invention, and (its structure can be braiding, knitting or non-braiding, as accessory fibers, and the natural fabric that comprises any kind, cotton thread etc. for example, or artificial fibre, polyamide etc. for example, the woven substrates that preferably comprises polyamide fiber), tufting fiber 114 is embedded in one or more layers tack coat 115, and tack coat 115 is attached to stabilized zone 116 (for example glass mat).Stabilized zone 116 adheres to pile layer 112 and cushion course 118, forms desirable carpet product 110.Main back sheet 113 of the present invention comprises this low-shrink polypropylene ribbon-like fibre, desirable low shrinkage characteristic is provided itself therefore for whole carpet product 110.Certainly, can use other common various variations in the interior fiber type (for example satin face fabric, short flannel etc.) of alternative back sheet structure and arrangement (for example increase of requirement or minimizing) and pile layer and carpet technology and the industry.For example, as the example of this carpet product, referring to U.S. Pat 6203881 or US6468623.

The fiber and the yarn product of invention

Following non-limiting example is represented the preferred embodiments of the present invention:

Example 1

On aforesaid standard production equipment, draw speed with 600 feet per minute clocks is made the carpet backing slit fibre, and specific as follows: 3.5-3.8 melt-flow homopolymer polypropylene resin (P4G32-050 of Huntsman) mixes with the multifunctional additive for lubricating oils that comprises 10%4-methyl D BS and 90%4 MFI sym-propene polymer resins.As shown in following table, change to mix and recently regulate final additive amount.This mixture that comprises PP resin and additive is extruded on the single-screw extruder and passes about 72 inches wide film die.Regulating the PP flow makes final tape thickness be about 0.002 inch.Fused film is quenched in the water of room temperature (about 25 ℃), flows to the cutting knife group by roller then, and cutting knife cuts into parallel strip with it.Working concentration is about the 4-methyl D BS (aka, p-methyl D BS) of 100ppm.Firm production, film is exactly transparent.The film that has cut slivering passes all with three big rollers of 110 feet per minute clocks operation, enters length about 14 feet and temperature then and is set in about 330 stove, and film is stretched in stove.Leave after the stove, film tape flows to other three rollers, and their speed of service is respectively 600,500,500 feet per minute clocks.By deep fat preceding two roller temperature are heated to 367 °F.These film tapes pass coil winding machine then, wind up them separately in coil winding machine.These finished films bars are called as the polypropylene ribbon fiber like this.

Produce several ribbon-like fibres by this way, regulate the blend range of concentrated additive-PP and regulate final additive amount.On MTS Sintech 10/G instrument, detect the tensile property of these ribbon-like fibres.Also by in 150 ℃ and 155 ℃ of hot-airs, measuring 5 10 " bar detects their shrinkage, promptly they is exposed in the stove lasting 5 minutes under said temperature, and remove these then and measure final lengths.With respect to its initial length, the average shrinkage of calculating described 5 bars is as shrinkage value.Also measure the concentration range of 4-methyl D BS in the ribbon-like fibre by gas chromatograph.For the different nucleator compound amount in the different fibers, all these outcome record are (DENIER is measured under Xg/9000m, and shrinkage factor is measured in 150 ℃ of hot-airs) in following table.

Table 1

The ribbon-like fibre yarn measured value of invention

Yarn # The nucleator consumption DENIER Shrinkage Percentage elongation Modulus Elasticity Toughness

1 (control) 0ppm 1218,0.8% 44% 14.07g/d 3.11g/d 0.87g/d

2 (control) 0ppm 1202,0.6% 44% 14.62g/d 3.22g/d 0.97g/d

3 82.9ppm 1220 0.1％ 45％ 14.46g/d 3.18g/d 0.91g/d

4 159.9ppm 1196 0.1％ 45％ 14.62g/d 3.24g/d 0.92g/d

5 196.2ppm 1206 0.1％ 44％ 14.82g/d 3.00g/d 0.86g/d

6 265.6ppm 1175 0.1％ 45％ 14.22g/d 3.13g/d 0.95g/d

7 345.4ppm 1166 0.8％ 47％ 14.79g/d 3.14g/d 0.94g/d

8 473.9ppm 1135 0.4％ 47％ 14.28g/d 3.03g/d 0.94g/d

9 549.1ppm 1144 0.4％ 44％ 14.05g/d 2.99g/d 0.89g/d

10 637.7ppm 1090 1.0％ 43％ 14.81g/d 3.13g/d 0.93g/d

11 739.0ppm 1081 0.8％ 45％ 14.62g/d 2.98g/d 0.92g/d

Therefore, fiber of the present invention provides fabulous low-shrinkage and good physical characteristic.

The X ray scattering analysis

By small angle x-ray scattering (SAXS) (SAXS), detect the long period interval of several above-mentioned yarns.The small angle x-ray scattering (SAXS) data are collected in Bruker AXS (Madison, WI) on the multi-thread detector of HI-Star, this detector is placed on the position of the sample 105cm in the Anton-Paar vacuum chamber, and vacuum chamber is evacuated to pressure and is no more than 100mTorr here.(40kV 40mA) produces X ray with the MacScience rotary anode

And focus on the 0.2mm size by three pin holes.Whole system (generator, detector, beampath, sample holder and software) can obtain from Bruker AXS company is commercial as single assembly.Through manufacturer recommendation, use silver-colored hydrochlorate (silver behenate) sample calibration detectors.

Typical data collection process is as follows.Prepare sample, reel for yarn on the 3mm brass tube that is drilled with the 2mm hole, is placed on this pipe in the Anton-Paar vacuum specimen chamber on the X-ray equipment, so that by described hole yarn is exposed to X-ray beam then.The path of X-ray beam of passing sample is between 2-3mm.Sample room and course of the beam are evacuated to less than 100mTorr, and sample was exposed to X-ray beam lasting 1 hour.Collect the 2-D data frame by detector, and proofread and correct Frame automatically by systems soft ware.In systems soft ware, use 2-pixel convolution that data are carried out smoothly before the integration.In order to obtain intensity scattering data [I (q)], use the software of manufacturer to utilize binary system summation method to exist as angle of scattering [2 θ] function ^TMGo up data are carried out integration, setting described software, to provide scope according to 0.01 ° of increment be 0.2 °-2.5 ° 2 θ.

Be exposed under such high temperature and collect data after lasting one and a half hours, and deduct a reference value, a reference value is to obtain by the class likelihood data that adopts no ribbon-like fibre sample on the position.Obtain scattering peak value center by the wedge (wedge) in conjunction with 60 degree on sample, described wedge is centered on the axle of definition ribbon-like fibre direction.Define peak value in two ways: or as near the position of the maximum quantity peak value center, or as the mean place of left side peak-peak and right-hand part peak-peak.The position of maximum quantity and central representation are in following table.

Table 2

The SAXS data of ribbon-like fibre of the present invention

Sample number maximum maximum position center

The quantity number of degrees number of degrees

0 261 0.275 0.2875

1 264.9 0.255 0.26

2 286.6 0.255 0.27

3 278 0.25 0.255

4 266.7 0.255 0.2675

5 260.2 0.255 0.2675

6 238.8 0.255 0.2725

7 233.5 0.255 0.2625

8 221.3 0.255 0.265

9 233.4 0.255 0.2575

10 237.4 0.255 0.2575

Then above-mentioned ribbon-like fibre yarn is woven in the basic carpet backing parts as the carpet fritter.With the cutting knife group this ribbon-like fibre is cut into the different in width band, so that make the DENIER measured value of yarn be about 1100 and 600.Twist 600 Denier yarns for about 168 inches according to per inch 24 one threads and beam overall.On Rapier looms, weave these distortion yarns and 1100 wideer Denier yarns then backing is provided according to 12 weft yarns of per inch.The firm bunch shape substrate (also being 18 inches wide) that is attached to of this backing (18 inches wide), just and then with liquid colourant and the facing surfaces of dyestuff printing backing own, last then synthetic is exposed under the baking temperature (about 130 ℃).The synthetic of finishing shows inapparent change in size subsequently.Comparatively speaking, the shrinkage factor that comprises the main backing performance of polypropylene ribbon fiber is about 4-5%, and the synthetic size of bunch shape substrate/main backing that will compare is thus dwindled similar quantity.Therefore, compare with the existing polypropylene ribbon fibre technology that the typical case of present use is conventional, the present invention obviously has the improvement of going up in fact.

Certainly also have many alternate embodiments of the present invention and improvement, they also should be included in the essence and scope of following claim.

Claims

1, a kind of polypropylene ribbon fiber, it comprises polypropylene and the nucleator compound of 10ppm at least, and show the TENSILE STRENGTH of at least 3 gram/DENIER, wherein said nucleator compound is from by p-MDBS, 3,4-DMDBS, 2,4, select in 5-TMDBS, DBS, Sodium Benzoate, NA-11, NA-21 and their group that any mixture constituted.

2, polypropylene ribbon fiber as claimed in claim 1, wherein said nucleator is p-MDBS.

3, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 1 at least.

4, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 2 at least.

5, fabric product as claimed in claim 3, wherein said product is a carpet backing.

6, fabric product as claimed in claim 4, wherein said product is a carpet backing.

7, a kind of polypropylene ribbon fiber, it comprises polypropylene and the nucleator compound of 10ppm at least, and be exposed to the shrinkage factor that shows after 150 ℃ of hot-airs less than 2%, and TENSILE STRENGTH is greater than 2.5 gram/DENIER, wherein said nucleator compound is from by p-MDBS, 3,4-DMDBS, 2,4 selects in 5-TMDBS, DBS, Sodium Benzoate, NA-11, NA-21 and their group that any mixture constituted.

8, polypropylene ribbon fiber as claimed in claim 7, wherein said nucleator is p-MDBS.

9, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 7 at least.

10, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 8 at least.

11, fabric product as claimed in claim 9, wherein said product is a carpet backing.

12, fabric product as claimed in claim 10, wherein said product is a carpet backing.

13, a kind of polypropylene ribbon fiber, it comprises polypropylene and the nucleator compound of 10ppm at least, and the X ray scattering pattern that shows makes scattering peak value center at 0.4 degree or lower, wherein said nucleator compound is from by p-MDBS, 3,4-DMDBS, 2,4, select in 5-TMDBS, DBS, Sodium Benzoate, NA-11, NA-21 and their group that any mixture constituted.

14, polypropylene ribbon fiber as claimed in claim 13, wherein said nucleator is p-MDBS.

15, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 13 at least.

16, a kind of fabric product comprises the polypropylene ribbon fiber described in the claim 14 at least.

17, fabric product as claimed in claim 15, wherein said product is a carpet backing.

18, fabric product as claimed in claim 16, wherein said product is a carpet backing.

19, a kind of method of making the polypropylene ribbon fiber comprises following sequential steps:

A) polypropylene formulations with heating is squeezed into film or pipe, comprises the nucleator compound of 2000ppm at the most in described polypropylene formulations;

B) immediately the film or the pipe of step " a " is quenched into a certain temperature, this temperature prevents the polypropylene crystal orientation in film or the pipe;

C) be used in the vertical cutting equipment of arranging of going up of described film or pipe and cut described film or pipe, thereby produce independent ribbon-like fibre thus; With

D) with at least 5: the described independent ribbon-like fibre of 1 draw ratio mechanical stretching, simultaneously described fiber is exposed under the temperature between 250 and 360, thus the polypropylene crystal orientation in the permission fiber.

20, the method described in claim 19, wherein the nucleation dosage that occurs in step " a " is 1500ppm at the most.

21, the method described in claim 19, wherein the nucleation dosage that occurs in step " a " is 1000ppm at the most.

22, the method described in claim 19, wherein the nucleation dosage that occurs in step " a " is 800ppm at the most.

23, the method described in claim 19, wherein the draft temperature of step " d " is between 260 °F and 330 °F.

24, the method described in claim 19, wherein the draft temperature of step " d " is between 270 °F and 300 °F.

25, the method described in claim 19, it further comprises following step:

(e) make the heat setting under the temperature of the draft temperature that surpasses step (d) of described ribbon-like fibre.

26, the method described in claim 25, wherein said heat-set temperature is between 300 °F and 380 °F.