CA2127015C

CA2127015C - Fiber reinforced functionalized polyolefin composites

Info

Publication number: CA2127015C
Application number: CA002127015A
Authority: CA
Inventors: Hendrik Theodorus Van De Grampel; Yongsheng Hou; Dennis Odell Spencer; Robert Gregory Swisher; Thomas Vincent Thimons
Original assignee: Azdel Inc
Current assignee: Azdel Inc
Priority date: 1993-10-29
Filing date: 1994-06-29
Publication date: 1999-06-08
Anticipated expiration: 2014-06-29
Also published as: KR0156771B1; JPH07179620A; CA2127015A1; EP0651003A1; KR950011115A; JP2564099B2

Abstract

A composite material consisting of continuous random glassmats with a new non-peroxide sizing chemistry, polypropylene and a functionalized polypropylene. This composite gives unexpectedly higher performance in bumper beam applications. The functionalized polypropylene contains anhydride functionalities, which are preferably maleic anhydride.

Description

~ 2 7 0 1 ~5 ..,~

8~ CATION

HBNDRI~ T. V~N DB ORA~PB~
~Or~wi ~
DENNI~ o. ~PBNCER
~ . 8~ BR
THOMA~ V. T~I~ON~

FIBER RBIhJOk~ ~NCTIoN~r.T~n POLYOL~FIN CO~rGel.~8 FIBLD O~ ~H~ IN~8NTION

The present invention relates to composite materials made from a polyolefin or polyolefins which have been chemically modified and reinforcing ~ibers which are laminated, not e~L~ded, into a composite material.

R~ ~J~D OY THB INVBNTION

Polypropylene i8 a popular thermoplastic resin becAllRe it is lightweight, yet stiff, resistant to chemicals and heat, and can withstand repeated flexing. Equally important, poly~r~ylene is lo less PYpPnRive than many other thermoplastics. As manufacturers look to new materials, polypropylene remains a front runner in thermoplastic applications. To improve sLLenyLh~ polypropylene has been reinforced with glass ~ibers. In automotive applications, polypropylene has been used for fan shrouds and battery cases.
But, as government mandated fuel economy standards become more stringent, auto makers are looking for ways to reduce weight while simultaneously increasing the crash worthineRs of their vehicles.
One way companies are meeting the government and concl~mer mandates is by using poly~u~ylene to replace metal and other plastics in automotive interiors and exteriors. This strategy has helped reduce both weight and cost while actually improving the recyclability of the vehicle.

Although polypropylene is known for its low cost and light weiqht, it has lagged behind metal and other plastic materials in terms of strength. While reinforcement with glass fibers can dramatically increase the strength and stiffness of polypropylene, its use in certain areas has been limited. Rese~rchers have sought .~l27al~
r ~
ways to further improve the properties of reinforced poly-propylene.
- Despite glass fibers being an excellent source of reinforcement, a major drawback is attributed to the lack of interaction between the polar surfaces of the glass fibers with the non-polar polypropylene. The result is a very weak filler/polymer interface.
After analyzing failures in composites of polypropylene and glass, it has been determined that the site of the failure is this weak interface. To combat this problem manufacturers have treated glass fibers, Qhortly after they are formed, with a composition, often called a size, which provides lubricating and protective properties to the fibers, and assists in providing strength and other properties to the rein~orced polymers and the products made therefrom. These sizing agents help to hold the glass bundles and reduce surface polarity of the glass.
One area where reinforced polypropylene has not done as well as other plastics is in the area of automotive bumper beams.
Traditionally, automotive bumpers have been made of metal, and until the low speed impact requirements were p~se~ into law for the 1974 model year most bumpers were made of metal. Once the new standards were p~se~, manufacturers started loo~ng for ways to meet these new requirements. An attractive alternative proved to be bumpers made of plastic. These new bumpers offered good protection from damage as well as having re~uce~ weight and improved corrosion resistance.

Automotive manufacturers sought improved bumper material which is strong, light and can retain its shape even when large units are molded. Thermoplastics in the polyolefin family are a favorite with molders, especially polypropylene. ~ er, when molded into a large piece such as a bumper beam or a fascia, poly~l~pylene is not sufficiently stiff to withstand a 5 mph impact from a vehicle.
Although polypropylene can be reinforced with glass fibers to improve its performance, even when rein~orced, poly~Lopylene falls short o~ meeting impact requirements demanded by auto manufacturers.

~ PTPTION OF TH~ PRIOR ART

Applicants are aware of the following U. S. Patents and publications concerning composite materials that include polyolefins, chemically modified polyolefins and reinforcing fibers.

~ 1 2 7 O ~ ~

US Pat. No. Inventor Issue Date Title '~_ 4,407,423 Iwanami 11-3-87 P R O C E S S F O R
PRODUCINGMOLDED
ARTICLE COMPRISING
HYDROTALCITE, EVOH, AND OLEFIN RESIN
4,755,575 Domeier 7-5-88 P R O C E S SF O R
PREPARINGFIBER
K~lN~u~CEDMOLDED
ARTICLES
4,882,229 Hwo 11-21-89 BT~NDS OF HIGH
MOLECULARWEIGHT
POLY~ ENE WITH
L O W D E N S I T Y
POLYPROPYLENE
4,943,607 TA~ e 7-24-90FIBBR-REINFORCED
U N S A T U R A T E D
POLY~Slh~
5,002,830 Gillis 3-26-91~l~k~uS ~lN~V
M A T E R I A L S
~ ATED WITH LOW
V I S C O S I T Y
POL~u~l AN~
U R E A F O R M I N G
COII~Cl~NTS
5,165,990 Nakano 11-24-92STAMPABLE SHEET
5,219,913 Tomomatsu 6-15-93 PO LY PRO PY LENE -BASED RESIN
COM~G~l lON
PAPERS
Title Author CHEMICAL COUPLING OF GLASS-FILLED R. C. Constable POLYPROPYLENE USING ACID OR A. M. Adur ANHYDRIDE MODIFIED POLYPROPYLENES
PERFORMANCE ENHAN~.. h~ IN GLASS Ashok M. Adur FIBER ~l~rORCED POLYPROPYLENE Robert C. Constable OB~AT~Fn BY THE ADDITION OF ACRYLIC Joseph A. Humenik ACID GRAFTED POLYPROPYLENE
POLYPROPYLENE Gail Elber Iwanami, US Patent 4,704,423, teaches a process for producing a molded article comprising a mixture of an olefin resin, which includes: a residual chlorine due to a Zeigler type catalyst; a hydrolyzed ethylene-vinyl acetate copolymer and a hydrotalcite compound. This patent does not teach the use of glass fiber, polypropylene or functionalized polypropylene.

O l S
Domeier, US Patent 4,755,575, teaches an improved process for the rapid fabrication of fiber reinforced thermoset resin articles having improved mold release characteristics and curable molding compo~ition~. While this patent teaches the use of fibers including fiberglass, it does not ~;~c~cs a glass mat application. This patent mentions the use of anhydrides specifically maleic and phthalic anhydrides, however, their use is connected with polyester and not-poly~.u~lene. A careful re~ing of this patent shows that it is dealing with reaction injection molding which differs substantially from the remolding of the composite plaques used in the p~es~n~ invention. No reference to poly~ lene is made.

Hwo, US Patent 4,882,229 te~rh~s a heat se~l~hle wrapping or pA~k~ng film which is c~p~hl~ of forming a re~Ahle seal. This patent is quite different from the invented ~lo~ess and the only note of interest would be the use o~ maleic anhydride to modify polyethylene. The present invention uses a modified polypropylene.

T~ ke, US Patent 4,943,607 teaches a fiber reinforced unsaturated polyester resin composite which, when proc~sse~, provides good molding. While this patent indicates that poly~u~ylene can be used, a polyethylene is preferable. The reinforcing fiber can be a glass fiber and even a glass mat. No mention is made in this patent of ~he use a functionalized polypropylene resin.

Gillis, US Patent S,002,830 deals with a reaction injection molding process which mentions the use of acid anhydrides as well as fibrous reinforcing material such as glass.

~ no, US Patent 5,165,990 te~ch~c a stampable sheet composition made from a ~y~ e polymer and fibrous reinforcing material. This patent alludes to the use of a maleic anhydride modified pol~Lvpylene and the use of polyp~upylene in conjunction with glass fiber fed into a hot press is disclosed. Additionally glass fibers which are oriented parallel to one another, in one direction is disclosed were glass fibers had previously been defined to include sheet or mat preparation. Powder fillers are ~ificll~se~, one of these being carbon black. While a number of individual points are mentioned there is no reference concerning the combination of these specific features into one composite or even that such a composite might be desirable.

21~701~

Tomomatsu, US Patent 5,219,913 teaches a composition of ~ polypropylene and talc powder and that this material is ideally suitable for an automotive bumper beam. It is noted that the polyolefins can be modified with maleic anhydride or acrylic acid.
Further organic fillers other than talc, such as glass fibers can also be used. However the combination of polypropylene and talc, is specified as the preferred combination.

Constable and Adur in their article entitled CHEMICAL COUPLING
OF GLASS-FILLED POLYPROPYLENE USING ACID OR ANHYDRIDE MODIFIED
POLYPROPYLENES describe a ~ -site p,o~ ced by injection molding polypropylene, short çhoppe~ glass fibers and anhydride modified polypropylene. This heated extrusion process pro~l~ces more intimate contact between the glass fibers and the thermal plastic.
It does not ~c-lcs laminates and a continuous glass mat would be impossible to extrude.

Adur, Constable and Humenik in their article entitled PERFORMANCE ENHANCEMENT IN GLASS FIBER K~lN~OK~U POLYPROPYLENE
OBT~TN~ BY THE ADDITION OF ACRYLIC ACID GRA MED POLYPROPYLENE
describe a composite produced by injection molding polypropylene, short c~oppe~ glass fibers and a chemically modified polyolefin, an acrylic acid modified polypropylene. The heated extrusion process described in this article achieves a more intimate contact between the glass fibers and the thermal plastic. This article does not ~sc~s laminates and a continuous glass mat would be impossible to extrude.

Elber gives some basic information about poly~-opylene in an article entitled POLYPROPYLENE. This reference's bearing on the invention only deals with some back~u~.d basics of one of the compositions components.

8FMM~Y OF THB INV~NTION

The invention provides a composition of material that can be used for an automotive bumper beams, automotive seat backing or other formed parts. In its basic form, the composite is a glass mat with a functionalized polyolefin. The preferred composite includes polyolefin, functionalized polyolefin and a glass fiber mat or chopped glass fibers of at least a half inch in length.

~2~
OBJ~CT~ OF T~B INVBNTION

The principal ob~ect of the invention is to provide an improved composite glass fiber and polyolefin sheet material.

A further object of this invention is to provide a composite material where the glass filaments don't have to be wetted out.

Another ob;ect of the invention is to provide a composite material which has superior dynamic strength.

Another ob~ect of the invention i8 to provide a ~_ site material with superior strength which can be pro~lce~ economically.

BRI_F D~R,C~TPTION OF TH~ DRA~IN~8 The foregoing and other ob~ects will become more readily apparent by referring to the following detailed description and appen~e~ drawings in which:

Figure 1 is a graph that shows the increase in performance of carbon black over a composite without carbon black using polypropylene and a glass mat with and without functionalized polypropylene;

Figure 2 is a graphical depiction of the increase in performance of a composite using both the functionalized polypropylene and new sizing over a c~ rOl material using standard polypropylene and existing sizing teçhnology.

DRTI~Tr.R~ RRrpTpq!ION

The present invention relates to composites made from contin1l0llc random glassmats with pol~u~lene in conjunction with a functionalized poly~u~ylene. Continllollc random glassmats are prepared with fiberglass having a uniform fiber size (e.g. X or T).
The fiberglass in the mat has been previously treated with a non-peroxide sizing.

The preferred aqueous size compositions for application to glass fibers for use in the invention contain, as essential components, a reaction product of a polymeric amine and an amine-~ ~ ~ 27Q ~ 5 ~
reactable organosilane, a ~ilm-forming polymer and an emulsified - polyolefin. ~he reaction product can be preformed or made in situ, and is preferably the product of a polyalkylene pol~ ~e and epoxy-funct1Qn~l alkoxysilane.

The reaction product can be obt~ine~ from a wide variety of polymeric amines and organosil~ , provided the polymeric amine contains at lea~t two and preferably three or more reactive amine yLOU~8, normally free primary or ~ec~n~Ary amine yL~u~s, and the org~os11An~ contains at least one amine-reAct~hle group.

ThQ preferred polymeric amines are those of the formula ~2N- ~C"~) -~

where n is 2 to 6 and x ~s 2 to 28, preferably 2 to 6. Such polyalkyleneamines include diethyl~.e~;amine, triethylene-tetramine, tetraethylenepentamine, pentaethylenehexamine, dipropyl~l.e~.iamine, tripropylenetetramine, te~.a~o~ylene-pentamine, pentapropyl~n~h~YAmine, and ~h~Y~ethyle~e~iamine.
Ni~u~es of these are also suitable and in many cases the polyalkyleneamine i8 chain-exten~A ~n the manner ~ e~ below.

Among other polymeric amines which can be usefully employed in the reaction product are polyamines cont~1n~n~ fatty acid moieties, polyamine-polyamides, acylated polyamines and other amidoamine polymers, con~encA~tion proA-~ts of polyalkylamines with poly~ nnAl acids, and polyalkyleneimines.

The polymeric amine component may also be chain-extçn~e~
variations of the foregoing, such as those pro~n~e~ by reacting the polyamine with difunctional materials which are reactive with amine ~vu~S to provide predominantly line~r compounds of increased molecnlAr weight. Compounds con~ni~g cArh~Yyl, ester, epoxy, isocyanates, halo or other moieties reactive with amine y-~u~S~ and especially diesters, diepoxies and diacids, can be used in this manner to effect chain extension.

A specific preferred polyamine is tetraethylenep~ntamine chain-exten~e~ with diethyl succinate and octanoic acid to a molecular weight of about 1500, sold as ~Alubraspin 230TM~ by PPG
Industries, Inc ~ The organosilane which is reacted with the polymeric amine to .~ ' .

~ ~ 2 7 ~ 1 ~

form the reaction product used herein is most commonly an - epoxy-functional alkoxysilane, i.e. a silane having at least one epoxy-functional organic moiety and up to three alkoxy yL~s. The hydrolysis product of the alkoxysilane, in which the alkoxy groups are at least partially hydrolyzed to hydLox~l groups, can also be used and is often preferred, although the hydrolysis is best carried out just prior to the reaction with the polymeric amine.
While alkoxy (or hydroxy) substituted silanes are readily available and are preferred, any organosilane that has at least one amine-reactable group, i.e. a group which reacts with the amine ~ou~s of the polymeric amine, can be used. The amine reactable group ~s preferably an epoxy group, but compounds containing amine-reactable keto yLuUyS~ isocyanato yLou~, ester ~LV~S, alkylhalo yL~S~ acryloxy yLuUyS~ and the like, may also be employed.

The pre~erred class of organosil~nP~ herein can be represented by the formula Rn-8i(OR~ n where R is the amine-reactable group, Rl is alkyl (preferably lower alkyl), or hydrogen (in the case of a hydrolysis product), and n is preferably one but may be 2 or 3. Some specific useful organosilanes are:
gamma-glycidoxymethyltrimethoxysilane delta-glycido~ybu~yltrimethoxysilane 3,4 e~oxy-~yclohexylethyltrimethoxysilane 3-(isocyanato)propyltriethoxysilane gamma-isocyanatopropyltriethoxysilane gamma-methacryloxypropyltrimethoxysilane gamma-acryloxy~L~yltriethoxysilane.

The proportions of polymeric amine and organosilane used to make the reaction product are usually from 0.1 to 25 moles of silane per mole of polymeric amine; preferably, the ratio provides for about one mole of organosilane per 1500 number average molecular weight of polymeric amine.

The reaction product can be preformed by mixing the polymeric amine and organosilane, with heating if desired to increase the rate of reaction. A solvent is not necess~ry unless the viscosity of the reactants is excessive, in which case an alcohol or water can be added. Alternatively, and ~l~u~lly preferably, the reaction product can be L~ .~d in si~u. i.e. by including polymeric amine and O~ Ar~ in She ~l~a~ing ~ tion- In thi~ case, they ; react during the r~ l~tion and/or ~ ng applicati~n of, the '~''~ ~ ,~-~tion to the fibers and the ~lh~equent drying. ~ ~ ~L

The ~ecnn~ c , .e~t of the ~ ~-sition i~ a water-di8p~r~ihle film-forming polymer. Film ~ormers ha~e been ~V~ n~lly used in size6 for:~iass fih~; for e~ca~le, ~-~L~ oil sizes are well kno~n for ~ n Po glass .f~h~~ for~1;P~le use (i.e. for use in woven ~hh~o or ~ t~ the ~es~l, i~lv~nt ~n~ ~tar~h is not 0 u1~ 7e~ as a~film-former.

S~he fi~form~ng polymer ~mponent herein is water~rs~hle and thus the-polymer i~;elf is ~s~lly o~ rel~tively low m~ r weight (by the term ~ ~r~:~hle~ is meant ~ll-hl~ or emu~ ff ~ e in ~a~d~3 . A wide ~ariety of water~ hl e film-for~ng polymRrs are ~nown and can be used. Ihe yLef~LLed polymers:are ~r~Y~c, hy whidh is m~ant compounds or mi~L~ of co~u~ having more than l.O epoxy yL~ per ~olecnle. These ~cl~l~e-polyglyc~dyl ether~ of poly~ D~ ~udh as h~rrh~nol A, or - o~ po1yhydr~c ~lC~h~l~; cyr-lc~l~rh~ poly~r~n~ c.; polymers c~ n~n~ ~e1~ e ~ ~-v~ -sudh as polyglycidyl acrylate; and t~e li~e. The yL~ ed ~p~Y~e~ are co~mercially av~l?hle ~L~ ~ A~ parff ~ ly polyglyciayl ~her~ of h~h~n~l a~ these often have ~eën ~ ~ fie~ to proViae aadi~n~?l fhn~t~n~l ~ty, a~ by r~t~on With ~e~ e~ to ~ e i~ ou~Lo y~u~s. The fi~ec~fic preferred fi~m fo ~ polymer i8 the epoxY resin sold by Rhone-Poulenc as Epi-Rez~ W60 5520, which is modified epoxy resin dispersion in water (56~ solids). The epoxy resin is understood to be a urethane-modified polyglycidyl ether of ~isphenol A having an epoxide equivalent of 520.

Also nce~l as the film-forming polymer are other synthetic - polymers made frcm various monomers and which, when dried or cured,form a surface film. Examples include polyvinyl ~alide polymers, acrylic polymers, ure~nes, alkyds, aminoplasts, vinyl acetate polymers and copolymers, poly(vinylpyrrolidone3, polyesters, and the li~e.

The composition also includes an em~lsified polyolefin, i.e., a stable dispersion of polyolefin in water. Preferred is emulsified polypropylene. Emulsions of polyolefins such as polyethylene and polypropylene are available commercially and are e~ployed in the practice of the invention. Preferred emulsions are B

2~ 27Q 1~
those of polypropylene which have been modified to introduce polar groups, as for example, by free-radical induced grafting ethyle~ic~lly unsaturated monomers, such as maleic anhydride or acrylic acid. Usll~lly, the level of such polar y ~u~s is quite low, in the rage of 0.01 to 1 percent by weight. For instance, ~ ~rcially avAil~hle maleic anhydride-modified poly~L~lene emulsions t~ lly contain about 0.1 ~ en~ by weight of maleic anhydride. a ~pec~ fic preferred polyolefin em~l ci~n iS ~old by National Starch and Chemical C y as Protolube RLf5440, and is a maleic anhydride modified poly~ lene emulsion contA;ning 32 percent ~oli~. Other examples of useful emulsified polyolefins lnclude ~everal products sold by Chemical C~L~oL~ion of America including those sold as Poly Emulsion 43N40, which is a non-ionic poly~ylene e~l~1on~ and Poly ~mul~ion 43C40, which is a ca~nn1c poly~ lene emulsion, each of these having about 40 percent ~ol1~c content.

An optional added component is a water-soluble, non-volatile c~rhQYylic acid. ~Non-volatile" is defined as a material which does not ~uLs~Ant~ ~11 y volatilize at the conditions at which the composition is made and applied. "Water-soluble~ is defined as a soluble in water in the co~ce~tration utilized in the composition.
Both of these terms being used in the sense conventional in the art. Unsaturated acids, such as maleic acid, are preferred, but others such as b~n~-oic acid, ~YAlic acid, butyric acid, methacrylic acid and the like can also be employed. The carboxylic acid component, while not critical, is important in achieving the desired level of properties in fabricated products made using the glass fibers treated with these compositions along with thermoplastic polymers such as poly~ ylene.

While the treating composition ~-C~ ly consists essentially of the foregoing components, other additives can be included. These may include such materials as surfactants and low molecular weight acids, such as acetic acid, used to adjust the pH, which is usually between about 3 and about 9, preferably between about 5 and 6.
Glass fibers treated with the foregoing size composition can be made into mats in accordance with known practice Such mats, especially continuous strand needled mats, are particularly useful for making the reinforced thermoplastic polyolefin resin sheets of the present invention These preferred size compositions for glass fiber treatment, substantially peroxide-free sizing agents comprise: a 2 1 27~
, , ~
polymeric amine having the formula H2N-(~,,~2,,N~X-H; an organosilane having the formula Rn-Si(OR1)4-n; a water-dispersible, film-forming polymer, defined as compounds having more than 1.0 epoxy groups per molecule; an emulsified polyolefin, such as emulsified polypropylene; and a carboxylic acid.

lOa The functionalized polypro ~ ene is prepared with maleic anhydride. While it is possible to use different materials in the functionalization of polypropylene, maleic anhydride is preferred because its works well and is low in cost. Basically, the functional group incorporated in the polypropylene chain is a 5 ~ hered ring. Position 1 of the ring contains an oxygen atom attached to an carbonyl carbon at position 2 which is attached to two more carbon atoms at positions 3 and 4 and finally to another carbonyl carbon at position 5.

CH2 CH CH \CH/ \ (~) C=O
2 2~C(~ o +H-O-H

~ , 0/

If any water is introduced into this system, it will have the tendency to cleave the ring between the oxygen atom (position 1), and one of the carbonyl carbons (either position 2 or 5). The water molecule will give up a posi~ively charged hydrogen ion which will attach to the now negatively charged oxygen atom at position 1. This will leave the other carbonyl carbon with a positive charge (see position 5). When the water molecule gave up a positive hydrogen proton it left a negatively charged OH ion, which is then attracted to the positive charge on the carbonyl carbon.

CH CH CH CH
CH/ \CH/ \CH/ \ i~(3)\ ~C+=O

~ \(j) ~- H-~-The result is that the ring is split and two carboxyl groups are formed. There is no indication that the anhydride or a compound containing two carboxyl functional groups differ any in perfo~ nce.

212 7~ t ~
~_ ~ CH3 Cl 3 C¦H3 1 ~(4~ ~

CH/ \ / \CH/ ~CH/(3)\ ~5~ --~

O \(1) H

What is important on the functionalized polypropylene is the number of functional ~ouys that are cont~ned in the polypropylene. This is generally measured in a weight/percent manner. Testing has shown tha~ a level of functionalization of at least .02% based on the weight of the entire composite increases the perfor ~nce of the composition. This level can be increased to 5% on weight. The optimal range is between .02% and .15% based on the final composition. This level can be achieved in two ways.
Either add polypropylene with the desired level of functionalization directly to the glass mat, or mix polypropylene with a highly functionalized polypropylene so that the end product will average out to the desired level of functionalization and add the blended mix to the glass mat.

When polypropylene is blended with functionalized polypropylene it is easier to let down a small quantity of functionalized polypropylene into the standard polypropylene.
Therefore, a higher degree of functionalization is desirable. It is now common in the industry to have 0.2% to 0.3% functionalized polypropylene. While polypropylene of this level of functionality can be used, it is preferable to use poly~ ylene with an anhydride functionality in the 0.8% to 1.6% range. Of importance is that at the 0.8% level of functionality there is no real difference in cost compared to material with a functionality in the 0.2% to 0.3% range. However, to obtain polypropylene with an anhydride functionality of 1.6%, the cost increases. This is generally due, not to the cost of raw materials, but rather to the processing cost involved in achieving the higher anhydride functionality. Further, material having a 1.6% anhydride functionality on the polypropylene is priced as a value added commodity.

The other important factor to consider in the selection of the 2 12 ~
polypropylene is the melt flow. Polypropylenes possessing a higher melt flow can be molded more easily while reducing energy costs to the purchAcer of the material.

After the composite product is produced, it is pre-cut into sheets called blanks. These blanks are pre-heated to a temperature just above their softening point. This is typically done with infra-red heaters in a holding apparatus which is connected to a modified mechanical stamping press. Softened blanks are then charged to an open, cooled matched metal die mounted in the press.
The die is then rapidly closed and the press is stopped on the bottom for 5 to 15 ~econ~R to allow for cooling of the laminate, the press is then opened and the part iB removed. Relatively complex isotropic parts requiring no trimming can be shApe~ at very high production rates in one die. This compares favorably with steel stampings which would generally require several "strikes~ in multiple dies and presses to stamp a comparable part.

ALTBRNaTIvE BMBODIMBNT8 While the present invention relates to composites made from continuous random E-glassmats (borosilicates) it is possible to further increase performance of the material by A~ng in uni-directional reinforcing strands of glass.

The use of Carbon Black has been shown to significantly increase the performance of the ~_ -site requiring less functionalized pol~ pylene be used, see Figure 1. This is a surprising f~n~ng. It had been expected that the addition of carbon black, a pigment, would at best cause no change in performance and at worst, result in a drop in performance. In theory, the pigment is dispersed in the polypropylene film, like the glass fibers. This ~isp~rsion of pigment in the film gives the composite color. However the pigment is thought to be inert, so that it is only trapped by the composite. While it is possible to use up to 20% or even 30% carbon black in the composite, the preferred range is between 0.01% to 5% carbon black.

While a glassmat, such as E-glassmat, is preferred, it is also possible to use chopped glass fibers of at least a half (1/2) inch in length treated with non-peroxide sizing, more specifically an aqueous composition of a polymeric amine and amine-reactable organosilane, along with a film-forming polymer, an emulsified polyolefin and a non-volatile carboxylic acid as described above 2~ ~7~1~
in relation to the sizing of glassmats for making the reinforced thermoplastic polyolefin plastic resin sheets of the present invention. The combination of these fibers with carbon black, polypropylene and functionalized polypropylene creates a composite material of superior performance.

- 2 l ~7~15 BXAMPL~8 ._ Material samples were prepared, an E-glassmat and polypropylene composite serving as a control against sample A, a composite of polypropylene, functionalized polypropylene and E-glassmat. When tested for Tensile Strength, Tensile Modulus, Flexural Strength and Flexural Nodulus, sample A showed improvements in all areas (see table 1) but Tensile Modulus. What was completely unexpected was the significant increase in performance when tested for impact. The impact tests were run on a Dynatup machine and showed an 83% increase in performance over the ~ol.~rol sample which did not USQ the ~unctionalized polypropylene.

T~bl~ 1 M~ANICAL PRO~ ~B
PROPFRTY unlts CONTROL A % IM~Ru~hMFNT
% GLASS % 40 40 TENSILE STRENGTH ksi 14.0 19.8 41 TENSILE MODULUSksi 800 800 --PLEXURAL STRENGTH ksi 24.0 29.6 23 FLEXURAL MODULUS ksi 800 900 13 IMPACT ft-lbs 16.0 29.2 83 A sample plaque was then prepared with carbon black, polypropylene, functionalized polypropylene and E-glassmat, sample B. The expectation was that the addition of carbon black would result in the same or slightly worse performance than the control.
However the addition of carbon black actually resulted in an increase in perfo~ ~nce of the plaque over both the control and sample A. Sample B showed a 14% improvement in Tensile Modulus and a 8% improvement in Flexural Modulus as shown in Table 2.

2 1 2 ~
Table 2 ._ .
~ ~ of CARBON BLAC~
PROPgRTY unit8 CONTROL A B % lll~Ruv~M~NT
TENSILE MODULUS ksi 800 800 914 14 FLEXURAL MODULUS ksi 800 900 974 8 CARBON BLACK Y/N NO NO YES

Based on this testing Bumper Beams were molded with the control composite and with a~ -site using maleated polypropylene carbon black and the new sizing chemistry on the glass mat. In all cases the bumpers ~howed a 20 to 60 percent improvement in static and dynamic 5 mph crash tests.

T~ble 3 BUMPER B~AN ~ RMANC~
N~x. Lo~d (lb8.) Deslgn Test Type 8t~n~-rdMA-PP % Improvement Generic static4,500 6,800 51 Domestic, Van statia8,000 9,800 23 Domestic, Sedan static 13,000 15,700 21 Foreign, Sedan static5,100 6,900 35 Domestic, Van 5 mph.21,000 33,700 60 Domestic, Sports 5 mph. 12,200 17,300 42 . .
MA-PP stands for maleated poly~opylene Samples were prepared with and without carbon black, with and without functionalized polypropylene, poly~upylene, a 30% glass mat with existing sizing teçhnology and with the new sizing technology. The results are listed in Table 4 below. The addition of the new sizing teçhnology demonstrated an appreciable difference in perfoL ~nce even without the functionalized polypropylene as can be seen by comparing the control with sample H. By removing the carbon black but ~ing functionalized polypropylene, sample I
shows a decrease in all areas compared to sample H which contained carbon black and the new sizing. Though sample I demonstrates 2~Ql~
improvements over the carbon black control without the sizing. The . sample contAin1ng carbon black, new sizing and functionalized polypropylene produced improved performance in every area.
T~ble 4 30% GLA88 FILLED BSP~RIM~NT
PROPBRTY unit8 CONTROL H I J
TENSILE STRENGTH ksi 12.o 12.5 12.0 13.4 FLEXURAL STRENGTH ksi. 20 23 22 25 FLEXURAL MODULUS ksi 620 806 747 853 ~RRoN BLAC~ Y/N YES YES NO YES
MA-PP NO NO YES YES
New Sizing NO YES YES YES

MA-PP stands for maleated poly~L~p~lene Applicants are aware that functionalized polypropylene combined with glass fiber reinforcement are known in the art.
However, what has been taught to date is the combination of functionalized polypropylene with short chopped fibers in an in~ection mold. The use of long chopped fibers, which are defined here to be fibers o~ at least one half (1/2) inch in length, or a glass mat significantly increases the impact strength ~of the composite, as can be seen in Table 5.

Table 5 INPACT STR~NGT~ (ft lbs/in) Data for 40% Glass filled polypropylene Short ChoppeA Long Chopped Continuous Continuous Injection Mat Mat MA-PP
Molded New Sizing l~ Compression Molded 2 10 1~ 16 MA-PP stands for maleated polypropylene ~12~

8UMNARY OF ~B A~n~v~NBNT
..
OF THB OBJBCT~ OF THE IN-~NTION

From the foregoing, it is readily apparent that we have invented an improved composite material which is especially suited for the production of automotive bumper beams. The combination of continuous random glassmats, with a new non-peroxide sizing chemistry, polypropylene and a functionalized poly~L~p~lene contAine~ anhydride functionalities have shown to give unexpectedly higher performance in bumper beam applications.

It is to be understood that the foregoing description and specific embodiments are merely illustrative of the best mode of the invention and the principles thereof, and that various modifications and additions may be made to the apparatus by those skilled in the art, without departing from the spirit and scope of this invention, which is therefore understood to be limited only by the scope of the appen~e~ claims.

Claims

1. A glass reinforced resin sheet comprising:
a continuous random glass fiber mat;
a polypropylene; and a functionalized polypropylene containing at least 0.02 percent of anhydride functionalities;
wherein the glass fibers in the continuous glass mat are treated with a substantially peroxide-free sizing agent; and wherein the sizing agent is an aqueous composition of a polymeric amine, an organosilane, a water-dispersible film-forming polymer and an emulsified polyolefin.

2. A resin sheet according to claim 1 further comprising carbon black.

3. A resin sheet according to claim 2 wherein the carbon black content is between 0.01 and 5.0% by weight of the resin sheet.

4. A resin sheet according to claim 1 wherein the functionalized polypropylene is functionalized with maleic anhydride.

5. A resin sheet according to claim 1 wherein the functionalized polypropylene has an anhydride functionality of 0.02 to 5.0% by weight.

6. A resin sheet according to claim 1 wherein the sizing agent further comprises a carboxylic acid.

7. A laminated composite comprising:
a continuous random glass mat having glass fibers treated with a substantially peroxide-free sizing agent;
a functionalized polypropylene containing at least 0.02% of anhydride functionalities; and a polypropylene;
wherein the substantially peroxide-free sizing agent comprises a polymeric amine, an organosilane, a water-dispersible film-forming polymer, and an emulsified polyolefin.

8. A laminated composite according to claim 7 wherein the functionalized polypropylene is functionalized with maleic anhydride.

9. A laminated composite according to claim 7 wherein the functionalized polypropylene has an anhydride functionality of 0.02 to 5.0% by weight.

10. A laminated composite according to claim 7 wherein the sizing agent further comprises a carboxylic acid.

11. A laminated composite according to claim 10 further comprising carbon black.

12. A laminated composite according to claim 11 wherein the carbon black content is between 0.01 to 5.0% by weight of the laminated composite.

13. A laminated composite according to claim 11 wherein the laminated composite is a bumper beam.

14. A laminated composite according to claim 13 wherein said glass mat contains uni-directional fibers.

15. A laminated composite comprising:
a continuous random glass mat having chopped glass fibers of at least 0.5 inch in length;
a functionalized polypropylene containing at least 0.02% of anhydride functionalities;
a polypropylene;
carbon black; and a substantially peroxide-free sizing agent comprising a polymeric amine, an organosilane, a water-dispersible film-forming polymer, and an emulsified polyolefin.

16. A laminated composite according to claim 15 wherein the functionalized polypropylene is functionalized with maleic anhydride.

17. A laminated composite according to claim 15 wherein the functionalized polypropylene has an anhydride functionality of 0.02 to 5.0% by weight.

18. A laminated composite according to claim 17 wherein the sizing agent further comprises a carboxylic acid.

19. A laminated composite according to claim 15 wherein the carbon black content is between 0.01 to 5.0% by weight of the resin sheet.

20. A bumper beam molded from a laminated composite comprising:
a continuous random glass mat having glass fibers treated with a substantially peroxide-free sizing agent;
a functionalized polypropylene containing at least 0.02% of anhydride functionalities; and a polypropylene;
wherein the substantially peroxide-free sizing agent comprises a polymeric amine, an organosilane, a water-dispersible film-forming polymer and an emulsified polyolefin.

21. A laminated composite bumper beam according to claim 20 wherein the functionalized polypropylene is functionalized with maleic anhydride.

22. A laminated composite bumper beam according to claim 21 wherein the functionalized polypropylene has an anhydride functionality of 0.02 to 5.0% by weight.

23. A laminated composite bumper beam according to claim 22 wherein the sizing agent further comprises a carboxylic acid.

24. A laminated composite bumper beam according to claim 23 further comprising carbon black.

25. A laminated composite according to claim 24 wherein the carbon black content is from 0.01 to 5.0% by weight of the laminated composite.