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Patent 2029726 Summary

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(12) Patent Application: (11) CA 2029726
(54) English Title: PROCESS FOR THE MANUFACTURE OF PRECOATED CELLULOSE FIBER CHARACTERIZED BY MIXTURES OF THERMOPLASTICS/SILICATE/ANHYDRIDE/ISOCYANATE AND COMPOSITES MADE FROM COATED FIBER AND POLYSTYRENE
(54) French Title: PROCEDE DE FABRICATION DE FIBRE DE CELLULOSE PREENDUITE, CARACTERISE PAR L'UTILISATION DE THERMOPLASTIQUES/DE SILICATE/D'ANHYDRIDE/D'ISOCYANATE ET COMPOSITES OBTENUS A PARTIR
Status: Deemed Abandoned and Beyond the Period of Reinstatement - Pending Response to Notice of Disregarded Communication
Bibliographic Data
(51) International Patent Classification (IPC):
  • C08L 1/02 (2006.01)
  • C08J 5/06 (2006.01)
  • C08L 25/06 (2006.01)
  • D06M 15/00 (2006.01)
(72) Inventors :
  • MALDAS, DEBESH CHANDRA (Canada)
  • KOKTA, BOHUSLAV V. (Canada)
(73) Owners :
  • DEBESH CHANDRA MALDAS
  • BOHUSLAV V. KOKTA
(71) Applicants :
  • DEBESH CHANDRA MALDAS (Canada)
  • BOHUSLAV V. KOKTA (Canada)
(74) Agent:
(74) Associate agent:
(45) Issued:
(22) Filed Date: 1990-11-13
(41) Open to Public Inspection: 1992-05-14
Examination requested: 1997-08-06
Availability of licence: N/A
Dedicated to the Public: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): No

(30) Application Priority Data: None

Abstracts

English Abstract


ABSTRACT
Under study were the method of preparation of coated cellulose fibers using
one or mixtures of thermoplastics (e.g. polyvinyl chloride, linear low density
polyethylene, medium density polyethylene, high density polyethylene and
polystyrene), coupling agent (e.g. phthalic anhydride or isocyanate), and/or Na-silicate. The composites thus prepared from coated fibers and polystyrene possess
improved mechanical properties.


Claims

Note: Claims are shown in the official language in which they were submitted.


CLAIMS
1. A treated discontinuous cellulose fibers comprising from 1 to 25% by weight of
polymer bonded to each other by reaction with 0.1 to 10% by weight of bonding
agent.
2. The treated fiber as defined in claim 1 wherein the coated polymer is any
grades of PVC.
3. The treated fiber as defined in claim 1 wherein the coated polymer is any
grades of polystyrene.
4. The treated fiber as defined in claim 1 wherein the coated polymer is linear low
density polyethylene.
5. The treated fiber as defined in claim 1 wherein the coated polymer is medium
density polyethylene.
6. The treated fiber as defined in claim 1 wherein the coated polymer is high
density polyethylene.
7. The treated fiber as defined in claim 1 wherein Na-silicate is a coating
ingredient.
8. The treated fiber as defined in claim 1 wherein the coated polymer is a mixture
of polymers as defined in claims 2 to 6.
13

9. The treated fiber as defined in claim 1 wherein a mixture of Na-silicate and
polymar as defined in claims 2 to 6, is a coating ingredient.
10. The treated fiber as defined in claim 1 wherein the bonding agent is phthalic
anhydride.
11. The treated fiber as defined in claim 1 wherein the bonding agent is
poly(methylene(polyphenyl isocyanate)}.
12. A composite from 1 to 50% by weight of precoated cellulose fibers as defined
in claims 1 to 11, dispersed in a matrix from 1-95% by weight of polystyrene,
and comprising from 0-50% by weight of plasticizer and from 0-40% by weight
of inorganic filler.
13. The composite as defined in claim 12 wherein the cellulosic fiber is selected
from softwood pulp or hardwood pulp or mixture of hardwood and softwood pulp
or sawdust or wood flour.
14. The composite as defined in claim 12 wherein the cellulosic fiber is selected
from non-wood plants, e.g. bagasse, nutshells, corn cobs, jute and the like.
15. The composite as defined in claim 12 wherein the inorganic filler material is
selected from mica, talc, calcium carbonate, silica, glass fibers, asbestos or
wollastone.
16. A compression molding made from a composite according to any of claims 12
to 15.
14

Description

Note: Descriptions are shown in the official language in which they were submitted.


2 ~ 7 ~ ~
BAt::KGlROUND OF TIIE INVENTlOl~d
This invention relates to a process of surface coating of natural cellulosic fibers
lU to improve their compatibility with thermoplastic matrix, and to composit~ materials
comprise the fibers thus surface coated and thermoplastic.
The present invention is based upon 1the concept that the dispersion of
continuous cellulose fibers into a polymeric matrix can be greatly improved by
.precoating of the fibers with a compatible polymer and a coupling ag~nt.
The published literature includes a number of proposals which teach th~
various way of dispersing and compatibilizing discontinuous cellulose fibers in
.thermoplastic matrix. Hamed, U.S. Patent number 3,943,û79 described the
pretreatment of cellulose fibers with a plastic polymer and a lubricant.
Goettler, U.S. Patent number 4,376,144 showed advantageous to combine the
bonding agent, like isocyanate, with th~ ccllulose fibers in a pre-treatment step of
cellulose-PVC composit0s.
Kokta, U.K. Patent number 2,193,503 adopted the pos~-coating procedura of
the cellulose fiber with polystyrene and isocyanat~ bonding agent before mixin~ the
cellulose fiber with polystyrane composites.
Hishida, U.K. Pat~nt number 2,090,503 d~scribed the surface coating of jut~
fibers with various coupling ag~nt, e.g. stearata, silane, titanata, acrylics and so on,
and prepared the composites of polypropylene and polystyrene.
(;aylord, U.S. Patent number 3,485,777 showad th~ compatibilization of ~raf~ed
cellulose fibers with polyvinyl chloride or polymethylmethacrylat~ matricas.
Gaylord, U.S. Patent number 3,645,939 also showed good compatibilization of
plastics, like polyethylsne, polyvinyl chloride or acrylic rubber with cellulose by
,orecoating the fibers with a thermoplastic, ethylenically unsaturated earboxylic acid
or acid and a free radical initiator.

2~2~37~
Coran et al., U.S. Patent numbar 4,323,625 prepared the composites comprise
discon~inuous cellulose fibers mixed with certain modified polymer, which have
methylol phenolic group grafted ther0to in prcsance of a bonding agent, like
isocyanate.
0 Eldin, Canadian Patent number 1,192,393 describes both or~anic and inorganic
fibers composites prepreg coated with two different resins, like rnaleic acid
(derivatives)/hydrantoin vinylether copolymers.
Kokta, U.K. Patent numbers 2,192,397; 2,192,398 and 2,203,743 describ0d the
precoating of celiulose fibers with a compatiblo polymer in pros~nce of silane or
isocyanate coupling ag~nts and tha composites of polyvinyl chlorid~ or polyetylene
and coated fibers.
Beshay, U.S. Patent number 4,717,742 reported the silane graftf3d cellulose
pulp and polyathylene composites.
Paturle, i~.K. Patent number 1,498,501 described the precoating of the
cellulose fillers with polyethyl or polypropyl~ne wax or a silicate and tha coated
particles being embeddad in th~ plastics eomponents.
Lachowicz et al., U.S. Patent numbar 4,107,11 û doscribed that a-c~llulos~
fibers, coated with graft copolymer comprising 1,2-polybutadine to which an acrylate
such as butylmethacrylate is grafted could be used in reinforcing of PE and other
plastic compositions.
Fujimura, Japan Patsnt Kokai number 137,243,178 described a cellulosic
material, e.g. straw, which has been acetylated with gasaous acetic anhydride as
reinforcing for polyolefins, like PE.
Kolbek, PCT Patent numb0r 422/81 described the coating of cellulosa fibers
with a mixture of YVC, silane coupling agent and organic solution, e.9.
tetrahydrofuran and dichloro methane.
Mtangi, U.S. Patent nurnber 4,647,324 deposited thermoplas~ic or thermoset
6 0 resin onto cellulose fibers, e.g. comminuted kraft paper or nswsprint in a dry

2~2~7~
process, and the coated fibers thus molded under heat and pressure io from
articles.
5UMMAP~Y OF THE INVENTION
It has now b~en found that the adhesiorl of discontinuous c~llulose fibars to
the polystyrene matrix can be promoted by post-coa~ing of cellulos~ fiber with amixture of thermoplastics or Na-silicate and a couplin~ agent such as phthalie
,0 anhydride of isocyanate.
According to pr0sent invention, the polymer used in tho coating ingredients
need not be the sam0 as that in the matrix, but should b~ csmpatible ther0with.
Polymers used as coating ingr0dients ara ~ith0r polyvinyl chlorid~, linear low density
polyethylene, medium d~nsity polyethylen0, high density polyethylene and
3 polystyrene or their mixtures (1:1 weight ratio). The coupling agents used are
phthalic anhydride (PHA) of the formula:
Il ,
o
and poly[methylene (polyphenyl isocyanate)] ~PMPPIC) ef the formula:
s~ I = C = O N = C = O N = C - O
~ _ CH2--t [~--c~z r ~ ~
(n = 2.7~

2~2r.r~2
DETAILED DESCRIPTION OF THE II~I'VENTION
The cellulosic material used in the invention includes callulosic fibers derived
from so~twood or/and hardwood pulps, e.g. chemical or m~chanical or chemi-
mechanical or r~fin~r or ston~ groundwood or th~rmo-m~chanical or chamith~rmo-
mechanical or explosion or low yield or high yield or ultra hi~h yield pulp, nut shells,
corn cobs, rice hulls, vegetable fibers, certain bambootype reeds, grasses, bagasse,
cotton, rayon (regenerated cellulose), sawdust, wood flour, wood shavings and the
like.
Preferred are cellulose fibers derived from wood sawdust, wood flour, wood
pulps, e.g. m~chanical pulps or chemith~rmomechanical aspan pulps. Ther0 arc
many available types of wood pulp which may be classified according to where they
30 were derived by chemical or mechanical or thermal treatments as well as known in
the pulp and paper industry. Waste pulp and/or recycled pulp can also bc used
The fibers have an aspact ratio (length divided by diameter) ranging from 2 to 5 for
sawdust, wood flour as well as for rnechanical pulps, and 15 to 50 for chemi-
mechanical and chemi-thermomechanical pulps, and 50 to 1~0 for low yield chemical
pulps (e.g. kraft, soda Dr bisulfi~e).
In some instances, it is desirabb to use mixtures of fibe~ having widely
different aspect ratios.
The polymer contained in the matrix is doscribed as bein~ "polystyrena" and
includes both polystyrene polymer and copolymer of a major proportion of
polystyrene with minor proportion of other vinyl polymer. The polymer "polystyrene"
includes polystyrene of different densities as well as different proportion of crystalline
and amorphous fractions.
The polymer contain~d in th3 coating ingredi~nt is described as being "vinyl
60 chloride polym0r" and includes both vinyl chloride polymer and copolyrner of a major

r~
proportion of vinyl chloride polymer with minor proportion of other copolymerizable
monomers such as vinyl acetate or vinyliclene chloride.
The polymer contained in the coating ingredient is described as being
"polyethylene" and includes both polyethylens polymer and copolymer of a major
proportion of polyethyl0ne with a minor proportion of other copolymers like
polypropylene. The polymer "polyethylene" includes linear low density polyethylene,
low density polyethylene, medium density polyethylene as well as high density
polyethylene prepared at low and high pressur0s.
:20 Both strongly basic silicates, with a pH in oxcess o~ 10.5, and weakly basic
silicates, e.g. a weakly basic sodium silicate, also termed a "n~utral" sodium silicate,
can be used to coat the cellulose fiber.
The ethylenically unsaturated carboxylic acid or anhydride coupling agent us~d
in the practice of this invention is preferably dicarboxylic such as phthalic anhydride,
ma!eic acid or anhydride, ~umaric acid, citraconic acid or itaconic acid. Phthalic
anhydride, which is identifiad as PHA, is the prHforred coupling agent.
Monocarboxylic acids, such as acrylic acid and methacrylic acid, may also be used.
The isocyanate coupling agent of tho invention is linear
poly[methylene(polyphenyl isocyanate)], which is identified as PMPPIC. The
PMPPIC can be of low, medium or high viscosity depending on degree of
polymerization, can be in analytical as well as technical grade. Other di-isocyanate,
e.g. toluene di-isocyanate, may also be used.
The surface -OH groups of celluloss and of its collnterpart lignin can !ink to
5 0 the anhydride groups of PHA, through th~ formation of either primary types of
linkage, e.g. es~er linkage, or secondary types of linkaga, e.g. hydrogen bonding.
However, the delocalized ~-electron of the benzene rings of both polystyrene and
phthalic anhydrida also provide strong interaction. In this way, PHA develops an
overlapping interface area betwe~n fiber and polymer matrices. Moreover, prior
coating of the fiber with polymer and PHA assists to form a sofl film of hyclrophobic

materials on the surface of the hydrophilic fibor. As a r~sult, the phase separation
between the two different matrices might be reduced. In addition, strong fiber-fiber
interaction due to intermolecular hydrsgen bonding has also been diluted, which
leads to better dispersion sf the fibers.
Likewise, PMPPIC is known as an efficierlt coupling agent which has the ability
to form covalent bonds with the fiber matrix as well as a strong interaction to the
polystyrene matrix through the ~-alectrons of the benzene ring present in both of
them. In the presence of PMPPIC and a th0rmoplastie or a mixture of
20 thermoplastics may form a soft coating of hydrophobic materials on the fiber surface.
As a result, the agglomeration of the hydrophilic cellulosic fib~rs diminishes, which
leads to better dispersion of the fillors into the thermoplastic matrix.
The combining of pre-coating ingrediants can be accomplished in an internal
mixer such as a Banbury mixar, Brabender mixer, CSI-max mixing extruder or on
30 Roll mill. The temperatures of mixing is a function of mixtures and equipment used.
The proportions of the ingredients are dictated by the r~sulting composite properties.
The amount of polymer/silicate used should be high ~nough to prevent fiber to fiber
interaction, usually at least 5 parts Gf a thermoplastic or silicate or a mixture of
thermplastics or a mixture of thermoplastic and silicate by weight per 10~ parts by
weight of wood fibers. Usually, no more than 10 parts of a thermoplastic/silicate or
their mixtures by weight per 100 parts of fibors by weight will be used, although
higher polymer/silicate levels of fiber pre-coating can be employed if desired.
The bonding agents are used in the coating ingredient of the invention in
so sufficient amount to achieve an adhesive bond b0tw6en th~ thermoplastics and the
cellulosic based fibers. This amount can b~ as littl~ as 0.1% by weight of cellulose
fiber, up to 10% by weight or more, on the same basis. The amount of bonding
agent required can also be expected to vary with the amount and nature of based
fiber present.

~ ~ s,~ ~ r,~ ~ ~
The fibers ones pre-coated with coating in~r~dients are mixed with polymer
matrix to form a composita usually in an internal mixer, extruder or in a roll mill.
Additional ingredients, such as fillers, plasticizers, stabilizers, colorants, etc., can
also be added at this point. Inorganic fill~rs material may be s~lected from mica,
talc, glass fibers, etc.
The following specific examples illustrate the use of coating ingredients, e.g.
polyvinyl chloride, linear low density polyethylene, medium density polyethylene, high
density polyethylene, polystyrene and Na-silicate as well as coupling agents (ph~halic
anhydride (PHA) and PMPPIC) for cellulose fibers.
~o
EXAMPLE I
High impact polystyrene (PS 525) was supplied by Polysar Limited, Sarnia,
Ontario, Canada, and PVC - Goodrich (Geon 110 x 334) was supplied by B.F.
Goodrich Geon Vinyl Division, Cleveland, Ohio, U.S.A.
3 Coupling agents: phthalic anhydride (PHA) was supplied by Anachemia,
Montréal, Canada.
Hardwood species aspen (Populus tremuloides Michx) was used in the form of
chemithermom~chanical pulp (CTMP). CTMP was preparod in a Sund Dafibrator
and have the proparties as describad in U.K. Patent numbcr 2,193,503 to Kokta.
CTMP aspen pulp was dried in an air circulating oven at 5~C for 48 hours
and then ground to a mesh size 6n mixture: 60.5%, mesh 60; 20.2%, mash 80;
15.5%, mesh 100; and 3.5%, mesh 2û0, with a Granu Grindar, C.W. Brabender,
Instruments Inc., U.S.A.
so
Coatinq treatment
Fibers ware coateci with PVC/PS ~5 (5-10 wt. % of fibsr) and PHA ~2-10 wt.
% of fiber) with lhe help of Laboratory Roll Mill (C.W. Brabender, Model No. 065) at
1 75C. The mixtures were collected and mixed repeatadly 8-10 times for
6~

~2~72~
homo~eneous coating. Finally, the coated fibers wore ground to mesh size 20.
Prep~ration olF th~ com~osi~es
Usually, a 25 gram mixture of coated c,el~ulosic fiber (15-35% by weight of
composite) were mixed in the roll mill at 1 75C. Aftar mixing 5-1 û times, th0
resulting mixtures were reground to rnesh siz~ 20. The mixturcs were then molded
(24 at a time) into shoulder-shaped test specimens (ASTM D-638, Type V).
Standard rnolding conditions are: temperature, 175C; pressur~ during heating and
.coolin~, 3.B MPa; heatin~ time, 20 rnin; cooling time, 15 min. Width and thickness
20 of each specimen were msasured with the help of a micrometer.
.Mechanical tests
The mechanical properties (e.g. tensile strangth at yiald point and tsnsile
modulus at 0.1% strain) of all the samples wsre measured with an Instron Tester
(Model 4201) following ASTM D-638 and rnechanical prop~rties wer~ automatically
calculated by a HP-86B computer. Th~ strain rate was 1.5 mm/min. Tho samples
were tested after conditioning a~ 23-~0.5C and ~O% R.H. for at ieast 18 hours in a
controlled atmosphere. Mechanical properties were reported after taking the
statistical average of six rneasurements. The coefficients of variation 2.5-8.5% wera
taken into accoun~ for each set of tests.
Tensile proper~ies of CTMP-PS 525 composites are præsen~ed in Table 1.
CTMP was coated with either PS 525 ~ PHA or PVC ~ PHA. Tensil~ properties of
composites filled with coated fibsrs are compared to that of virgin polystyrsne as
50 well as to that fillad with non-coated CTMP. It is obvious, that the strength of
coated fiber-filled composites is superior to that of non-coated fiber-filled composites,
and it increases with the rise in concentration of the coupling agent (e.~. phthalic
anhydride) at the initial stage, and then decreasas wi~h the higher percentages of
fiber level. At 25% of fiber addition, the strerl~th has increased from 16.8 MPa to

24.2 in case of PVC (10 wt. /O) ~ PHA (2 wt. /O~, and to 22.7 for PVC (10 wt. %)
PHA (5 wt. %).
Modulus of the coated fiber-filled compositss incr~ases with th~ increase in
fiber content of the composites, and its value Isxc~eds that of the original and non-
coated fiber-filled composites, particularly wherl higher fibar loading (e.g. 35 un~ %)
is considered.
P\/C + PHA is a better coating combination compar2d to polystyrene ~ P~iA
mixtures.
20 EXAMPLE ll
The composites wsre prepared and evaluatad as described in Example 1, but
CTMP aspen was substituted by sawdust asp0n. Chips for making sawdust were
dried in an air circulating oven at 55C; for 48 hours and thsn ground ~G a mesh
size 60 mixture: 60.~%, mesh 60; 20.2%, mesh 30; 15.5%, mesh 100; and 3.5%,
mesh ~00, with a ~;ranu Grinder, C.W. Brabender, Instruments Inc., U.S.A.
It appears from Table ll that a!l both tensil~ strength and ~ansile modulus
follow more or less the sinnilar trend as discussed in Example 1.
40 EXAMPLE IIJ
The composites were prepar~d and evaluated as described in Example 1, but
CTMP aspen was substituted by sawdust spruc~. Sof~wood species mixtures (75%
black spruce, 20% balsam and 5% asp~n) was used in the form of wood flour
(sawdust). Sawdust was preparad from tho chips as describecl in Example ll.
50 Tensile results are presen~ed in Table ill. This table indicates that the properties of
the coated fiber-filled ~omposites aro generally superior to ~he original polymer with
some exception, and except for modulus, tensile strength increases ~ven comparecl
to non-coated fiber-fillsd compositas. The maximum improvem~nts in rnechanical
properties, except those of modulus which incrcases continuously with th~ addition

2 ~ 7 ~
of more and more fibers to the composites, occur between 15% and 25/9 fiber
content, but in a few cases thosa occur at even 35%. Moreover, propcrties improve
more when PVC is usad as a coating componant compar~d to that of PS 525.
EXAMPLE IV
Ths composites of CTMP asp0n, sawdust aspan and sawdust sprucq-filled
polystyrcne wer~ prepared as indicated in Exampl~ 1, but polystyrena usod at this
time was hi~h heat crystal polystyrenc (PS 201) of Poiysar Limited, Sarnia, Ontario,
Canada. All these fibers were~ precoated with ~ither PS 201 (10 wt. %) + PHA (2-
21~ 10 wt. %) or PS 525 (10 w~. % ~ PtlA (2-10 wt. /O). Her0 ~he machanical
properties under study is the impact strength (Izod, un-notched) which was tested
with an Irnpact Tester (Model TMI, No. 43-01) of Testin~ Machin0s Inc., U.S.A.
The impact strength of the ~omposito materials is shown in Tabla IV. This
table reveals that the irnpact strength of the PS 201 bascd composites considerable
improves up to 25%-35% of fiber loading whan fibers (CTMP aspen/sawdust
aspen/sawdust spruce) were precoated with PS 201 and 2% or 5/~ of PHA.
EXAi!APLE V
The cornposites of CTMP aspen-fiiled polystyrene (PS 201) were prepared and
evaluated as indicated in Example 1, but C:TMP was being precoated with mixturesof PS 525/PVC and or Na-silicatt~ (5-10 wt. % by wcight of fiber), and PMPPIC (8wt. % by weight of fibet). Na-silicate was supplied by Anachemia, Montréal,
Canada, and poly[methylene (polyphenyl isocyanate)~ (PMPPIC) was supplied by
50 Polysciences Inc., U.S.A.
The tensile results are presented in Tablt~ V. Tabl~ V reveals that the strengthof coated CTMP-filled ct)mposit~s, except tha~ of PVC coated fiber-ones, improved
compared to the non-coated CTMP-filled composit~s. But strength of tha compositematerials cornprising 10% PS 525 ~ 8% PMPPIC as coatin~ components irnproved

2 ~
best only up to 25% of iiber lavel compar~d to evon that of original polymer.
Modulus of coated tiber-fillod composites are superior to those of the original
composites and in some cases to those of non-coat6d fiber-fill~d composites.
EXAMPL Vl
The composites of CTMP aspen-filled polystyrene (PS 201) were prepared as
indicated in Example 1, evaluated as indicated in Exampl~ IV, and CTMP was beingprecoated as described in Exampl~ V. The Izod impact strength of composite
materials is shown in Table Vl. The impact strength of tho original polymer
20 reduces, in general, due to the addition of wood fibers. But, Ih~ impact strength
improves compared to non-treated fiber-filled composites, particularly when coupling
agent isocyanate is used. Furtherrnore, the impact s~rength of silicate and PMMPIC
treated PS 201 - CTMP composites improved up to 35% of fib~r 10vsl comparad to
the original polymer.
EXAMPLE Vll
The composites o~ CTMP aspsn-filled polystyrene (PS 201) were prepared and
evaluated as indicated in Example 1, but CTMP was boing pracoated with mixtures
of different grades of polyethylenes, e.g. LLDPE, MDPE and HDPE, PS 525 (5-10
wt. % by wei~ht of fiber), and PMPPIC ~8 wt. % by weight of fiber). Linear low
density polyethylene (LLDPE) Novapol GF-0118-A and a high density polyethylene
(HDPE) GRSN-8907 wara supplied by Novacor Chemical Ltd. Modium density
polyethylene (MDPE) GlL-560-i3 was supplied by CIL.
5~ The tensile results ars prssented in Tablc Vll. It is obvious from this table that
polystyren~ itself is a better partner for PMPPIC as a coating camponent for
polystyrene-based composites. Polyethylene along wi~h PMPPIC showed some
positive influence. The strength of the oomposites containin~ 25% of fiber coated
with 10% HDPE and Pi~APPlC, improved compared to ~hat of the originai polymer

and of non-coated fib~r-fill~d composites. Althou0h the stren~th of all the other
composites is inferior to that of ori~inal polymer, the stren0th of the composites
containing a lower 1~3v21 of fibers (~.g. 15%), which were coated with ~ithsr MDPE or
HDPE along with PMPPIC, is superior to not-coated fiber-filled composites. In
general, modulus of fiber-filled composites incraased comparad to the original
polymer. HDPE + PMPPIC coated fiber-fill~d oomposites showsd the b0st
improvements even when compared to non-coated tib0r-fill0d composites.
EXAMPLE Vlll
The composites of CTMP aspen-filled polys~yrene (PS 201) ware prepared as
indicated in Example 1, evaluated as indicated in Example IV, and CTMP was beingprecoated as describsd in Example Vl. The Izod impact str0ngth of composite
materials is shown in Tabl~ Vlll. It is revealed from this tabl~ that the impactstrength improves when fibers were coated with PMPPIC and rnixtur~s of
polyethylen~ and polystyrene. Moreover, compar~d to non-coated fiber-fill0d
cornposites, the impact str0ngth of the same compositss impraves in many cases.
4 0
5~

~2~7~
17. An infecRon molding made trom a cornposit~ accorcling to any of claims 12 to 15.
REFERENCE5
1. Gaylord, N.G., U.S. Patent, 3,485,777, Dsc. 23,1969.
2. Gaylord, N.G., U.S. Patent, 3,645,939, Feb. 29, 1972.
3. Hamed, P., U.S. Patent, 3,943,079, March 15, 1976.
4. Imagawa, T. and Endo, N., lJ.S. Patent, 4,029,847, June 14, 1977.
5. Paturle, S.A., U.K. Patent, 1,498,501, Jan. 18, 1978.
6. Lachowicz, D.R. and llold~r, C.B., U.S. Patent, 4,107,110, Au~. 15, 1978.
7. Fujimura, T. and Suto, S.l., Japan Patent, Kokai, 137,~43/78, Nov. 30, 1978.
8. Holbek, K., PCT Patent, 422/81, Feb. 19, 1981.
9. Hishida, i., U.K. Patent, 2,090,849, Jul~ 21, 1982.
10. Koran, A.Y., U.S. Patent, R., 4,323,625, Apr. 6,1982.
11. Goettler, L.A., U.S. Pa~nt, 4,376,144, March 8,1983.
12. Coran, A.Y. and Goettler, L.A., U.S. Pat~nt, 4,414,~67, Nov. 8, 1983.
13. Eidin, S.H., Canadian Patent, 1,192,102, Aug. 20, 1985.
14. Mtangi, S.A. and Fishman, D.i~l., U.S. Patent, 4,647,324, March 3,1987.
15. Beshay, A.D., U.S. Patent, 4,717,742, Jan. 5, 1988.
16. Kokta, B.V. and Béland, P., U.K. P~ent, 2,192,398, Jan. 13, 1988.
17. Kokta, B.V., U.K. Pat~nts: 2,192,397, Jan. 13, 19BB; 2,193,503, Feb. 10, 1988;
2,203,743, Oct. 26, 1988.

r~
TABLE I
Composition of Polym~r/ Strength Modulus
Coated Materials~ Fiber (MPa~ (~Pa)
Polymer PHA W~ight % of IFib~r
3~ 15 25 35
, "..,,..,.~
- - PS 525 16.8 1.4
- - CTMP aspan 18.9 22.3 21.5 1.8 2.0 2.3
PS 525 (10%) 2% S::TMP aspen 19.1 19.4 21.2 1.4 1.7 1.7
-PS 525 (10%) 5% CTMP aspen 18.9 19.6 19.0 1.5 1.7 1.8
PS 525 (10%) 10% CTMP aspen 19.7 20.0 1.5 1.5 1.7 1.9
PVC (10%) 2% crMp aspen 21.4 24.2 21.5 1.6 1.9 1.9
PVC (10%) 5% CTMP aspen 19.5 22.7 20.9 1.5 1.8 1.9
PVC (10%) 10% CTMP asp0n 20.3 21.1 22.1 1.6 1.g 2.0
.... _ :
~By weight of fiber.
TABLE~ ll
. . _ ~
Composition of Polym~r/ Stren~th Modulus
Coated Materials~ Fiber (MPa) ((~iP~)
4 0 - - - - --- -- -- -. . _ _
Polymer PHA Weight % of Fiber
25 35 1 S 25 35
~ . . _ _ _ ,
- - PS 525 16.8 ~.4
- - Sawdust asp~n 16.2 18.317.2 1.6 1.8 2.0
PS 525 (10%~ 2% Sawdust aspen 17.9 17.818.9 1.5 1.7 1.7
PS 525 (10%) 5% Sawdust aspen 17.2 16.816.4 1.3 1.5 1.7
PS 525 (10%) 10% Sawdust aspen 19.4 17.316.0 1.7 1.7 1.8
PVC ~10%) 2% Sawdust aspen 18.3 19.317.9 1.6 1.8 1.8
PVC (10%) 5% Sawdust aspen 19.4 19.720.9 1.6 1.6 1.9
PVC (10%~ 10% Sawdust asp~n 19.3 19.017.5 1.4 1.6 1.8
60 *By weight of fiber.
~ '

~32~72~
TAE3LE 111
Composition of Polymer/ Strength Modulus
Coated Materialsh Fiber (MPa) (~Pa)
~ . _ . .. _ .. ,
Polymer PHA W~ight % of Fib~r
25 35
1 o
- - PS 525 16.8 1.
- - Sawdust spruce 17.2 18.2 17.8 1.7 1.92.0
PS 525 (10%)2% Sawdust spruc~ 15.5 17.5 18.7 1.4 1.51.8
PS 525 (10%)5% Sawdust spruce 18.1 20.2 18.7 1.4 1.61.6
PS 575 (10%)10% Sawdust sprucs 19.6 19.8 1~.2 1.5 1.61.g
PVC (10%) 2% Sawdust sprucc 19.3 19.6 23.5 1.6 1.72.0
PVC (10%) 5% Sawdust spruce 19.4 l9.0 18.8 1.6 1.81.8
pVC (10%) 10% Sawdust spruce 19.2 19.7 21.3 1.5 1.61.9
*By wei~ht of fiber.
~ '
':

~2~7~
TABLE IV
Compositions of Polym~r/
Coated Matenals~ Fiber Izod Impact Strength (J/m)
Polymer PtlA Wcight % of Fiber
- - PS 201 7.8
- - CTMP asp0n 6.3 6.1 4.9
PS 201 (10%) 2% CTMP aspen 6.1 9.1 5.4
.PS 201 (10%) 5% CTMP asp~n 9.9 9.6 8.7
PS 201 (10%) 10% CTMP aspen 6.8 7.8 9.3
PS 525 (10%) 2% CTMP asp~n 6.5 5.8 5.8
PS 525 (10%) 5% CTMP aspen 8.0 6.4 6.3
PS 525 (10%) 10% CTMP aspan 6.2 6.3 5.8
- - Sawdust aspen 6.9 6.6 6.2
PS 201 (10%) 2% Sawdust aspen 8.7 6.4 7.7
PS 201 (10%) 5% Sawdust aspen 11.0 10.5 10.9
PS 201 (10%) 10% Sawdust aspen 5.6 6.5 9.7
PS 525 (10%) ~% Sawdust aspen 6.4 6.3 6.2
PS 525 (10%) 5% Sawdust aspan 6.0 ~.9 5.8
PS 525 (10%) 10% Sawdust aspen ~.8 5.8 5.4
- - Sawdust spruce 6.5 6.3 5.8
PS 201 (10%) 2% Sawclust spruce 8.7 9.9 9.0
PS 201 (10%) 5% Sawdust spruce 8.3 10.1 5.8
PS 201 (10%) 10% Sawdust spruce 6.3 7.2 5.9
PS 525 (10%) 2% Sawdust spruce 7.1 7.0 6.3
PS 525 (10%) 5/O Saw~ust spruce 6.1 6.4 5 8
PS 525 (10%) 10% Sawdust spruce 6.3 5.9 5.8
50 ~By weight of fiber

2~29 1J7,~i
TABLE~ V
Composition of Strength Modulus
Coated Materials~ (MPa) (~Pa)
_ _ . , . . _
Weight % of Fiber 15 25 35 15 25 35
10 Polymar PMPPIC
_ _ _ _ _ _ . . . _ . _ _ . . .
~ 41.5 1.9
*~ 36.0 35.8 33.8 1.9 2.0 2.2
PVC (10%) - - 28.1 2g.4 30.2 2.1 2.2 2.4
PVC (10%) - 8% 39.1 40.7 37.3 2.1 2.2 2.3
PS 525 ~10%) - - 32.1 33.9 27.3 2.0 2.2 2.5
PS 525 (10%) - 8% 36.8 37.9 40.0 2.1 2.2 2.5
PVC (5%) PS 525 (5%) 8% 41.1 38.1 35.0 2.1 2.2 2.a,
Silicate (10%) - - 33.1 27.7 26.3 1.9 2.1 2.4
Silicate (10%) - ~% 39.3 40.6 39.9 2.1 2.4 2.4
Silicate (5%)PS 525 (5%) - 30.7 31.1 30.0 2.0 2.1 2.4
Silicate (5%)PS 525 (5%) 8% 37.1 37.4 33.7 2.0 2.1 2.5
PS 525 (10%) - 8% 42.7 48.7 46.4 1.9 2.1 2.2
,
~By weight of fib~r. ~Only PS 201. ~Non-coated CTMP.
3~ :

2~726
TAE~LE~ Vl
... . _ . . _ . . .
Compositions o
Coated Materials~ Izod Impact Str~n~th (J/m)
Weight % of Fiber 15 25 35
Polymer PMPPIC
. _ _ _ _ ..... .
b ~ 7 . 8
~ 6.3 6.1 4.9
0 PV~ (10%) - - 5.7 5.7 6.4
PVC (10%) - 8% 5.7 6.0 6.0
PVC (5%)PS 525 (5%~ 8% 6.6 6.6 5.6
Silicate (10%) - - 5.8 6.8 4.2
Silicate (10) - 8% 6.5 9.4 9.9
Silicate (5%) PS 525 (5%) - 6.3 6.4 5.1
Silicate (5%) PS 525 (5%) 8% 6.2 6.1 5.7
PS ~25 (10) - 8% 5.4 5.6 6.9
_.
*By weight of fiber. ~Only PS 201. *~Non-coat~d CTMP.
~o

7 2 ~
TABLE Vl3
Composition o7 Strength Modulus
Coated Materials7 (MPa) (GPa)
Weight % of Fiber 15 25 35 15 25 35
10Polymer PMPPIC
".. ._ . ~ -- _
*~ 41.5 1.9
~ 36.0 35.1 33.8 1.9 2.0 2.2
20 LLDPE (10%) - - 27.2 27.6 24.4 2.0 ?.1 2.2
LLDPE (10%) ~ 8% 30.3 33.~3 27.8 1.9 2.() 2.1
MDPE (1C)%) - - 33.6 31.5 23.1 1.8 1.9 2.0
MDPE (10%) ~ 8% 38.2 34.4 25.5 1.9 2.0 2.1
LLDPE (5%)MDPE (~i%) 8% 37.5 29.1 25.3 1.8 1.9 2.1
HDPE (10%) - - 29.2 26.7 23.5 2.0 2.0 2.1
HDPE (10%) ~ 8% 38.2 45.4 30.9 2.0 2.1 2.3
LLDPE (5%)HDPE (5%) 8% 37.1 31.8 27.1 1.9 2.0 2.3
MDPE (5%)HDPE (5%) 8% 38.2 30.3 25.4 2.0 2.1 2.1
PS 525 (5%)LLDPE (5%~ 8% 30.5 31.8 29.5 2.0 2.2 2.2
PS 52~; (5%)MDPE (5%) 8% 38.4 31.8 31.0 2.0 2.1 2.2
PS 525 (5%)I-IDPE (~%) 8% 33.5 36.3 30.4 2.1 2.2 2.3
PS 525 (iO%~ - ~3% 36.8 37.9 40.0 2.1 2.3 2.5
~By weight of fib~r. ~bOnly PS 201. ~*~Non-coat~d CTMP.
,~e .

2~297~6
TABLE Ylll
Compositions of
Coated Materials~ Izod Impact St~ngth (J/m)
W~ight % of Fibar 15 25 35
1 uPolymer PMPPIC
.. _ ... . .. . _ . . _
7.8
**~ 6.3 6.1 4.9
LLDPE (10%) - - 5.8 6.5 5.7
~ LLDPE (10%) - 8% 7.3 6.4 6.8
MDPE (10%) - - 6.7 8.6 6.4
MDPE (10%) - 8% 7.0 6.9 6.7
LLDPE (5%)MDPE (5%) 8% 6.4 6.9 7.7
HDPE (10%) - - 7.6 6.2 5.5
HDPE (10%) - 8% 7.7 8.2 6.7
LLDPE (5%)HDPE (5%) 8% 9.3 10.1 5.2
MDPE (5%)HDPE (5%) 8% 7.2 7.9 9.8
PS 525 (5%)LLDPE (5%) 8% 8.5 7.0 5.6
PS 525 (5%)MDPE (5%) 8% 7.~ 7.2 6.8
PS 525 (5%)HDPE (5%) 8% 8.6 7.3 6.3
PS 525 (10%) - 8% 5.4 5.6 6.9
4 o
*By weight of fiber. ~*Only PS 201. ~Non-coaled CTMP.
5~
':

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Administrative Status

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Event History

Description Date
Application Not Reinstated by Deadline 2003-07-18
Inactive: Dead - No reply to s.30(2) Rules requisition 2003-07-18
Inactive: Abandoned - No reply to s.30(2) Rules requisition 2002-07-18
Inactive: S.30(2) Rules - Examiner requisition 2002-01-18
Letter Sent 1997-12-05
Inactive: Status info is complete as of Log entry date 1997-08-28
Letter Sent 1997-08-28
Inactive: Application prosecuted on TS as of Log entry date 1997-08-28
Inactive: Applicant deleted 1997-08-28
Inactive: Applicant deleted 1997-08-28
Inactive: Inventor deleted 1997-08-28
Inactive: Inventor deleted 1997-08-28
Request for Examination Requirements Determined Compliant 1997-08-06
All Requirements for Examination Determined Compliant 1997-08-06
Application Published (Open to Public Inspection) 1992-05-14

Abandonment History

There is no abandonment history.

Maintenance Fee

The last payment was received on 2002-08-30

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  • the reinstatement fee;
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Fee History

Fee Type Anniversary Year Due Date Paid Date
MF (application, 8th anniv.) - small 08 1998-11-13 1997-07-30
Request for examination - small 1997-08-06
MF (application, 9th anniv.) - small 09 1999-11-15 1999-09-07
MF (application, 10th anniv.) - small 10 2000-11-13 2000-09-11
MF (application, 11th anniv.) - small 11 2001-11-13 2001-10-09
MF (application, 12th anniv.) - small 12 2002-11-13 2002-08-30
Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
DEBESH CHANDRA MALDAS
BOHUSLAV V. KOKTA
Past Owners on Record
None
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Cover Page 1994-04-04 1 18
Claims 1994-04-04 2 48
Description 1994-04-04 20 666
Abstract 1994-04-04 1 12
Reminder - Request for Examination 1997-07-13 1 117
Acknowledgement of Request for Examination 1997-12-05 1 179
Notice: Maintenance Fee Reminder 1999-08-17 1 130
Notice: Maintenance Fee Reminder 2000-08-15 1 119
Notice: Maintenance Fee Reminder 2001-08-14 1 131
Notice: Maintenance Fee Reminder 2002-08-14 1 118
Courtesy - Abandonment Letter (R30(2)) 2002-09-26 1 170
Notice: Maintenance Fee Reminder 2003-08-14 1 115
Fees 2000-09-11 1 24
Fees 2001-10-09 1 22
Fees 2002-08-30 1 24
Fees 1996-07-26 1 41
Fees 1995-08-22 1 59
Fees 1994-08-08 1 78
Fees 1995-03-20 1 62
Fees 1992-10-29 1 56
Fees 1993-10-25 1 53
Correspondence 1993-04-08 1 21